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The Origin of The 'Shmup' Genre: A Historical Study

This is the result of playing nearly 3500 arcade games over a 4 year period in order to trace the genealogy of one of the most important genres of all times.

Luke McMillan, Blogger

February 6, 2013

51 Min Read


In 2003 I began research for my PhD topic. As part of my research, I began to explore the family tree of the Shmup genre, the oldest and most profilific genre of gaming (within the context of the arcade medium). Using MAME, A Yahoo Auctions Japan account & a Sega Astro City Arcade machine I began to trace the origins of this genre by playing over 3,500 arcade games.

This blog post is an excerpt from the final dissertation which explores the origins of the Shmup genre and examines the games which set the standards that we accept today.

I thought it would be fitting to publish this work as a blog post now that it is a decade old and use this to reflect on the research and how it was conducted. I will present the chapter in it's entirity, as it was publsihed and then provide some quick reflection on the process at the end.


Defining the Shmup

While contentious, it is widely believed that the first published instance of the word ‘Shmup’ was in Commodore 64 magazine, Zzap!64 Issue 3, July 1985. The word was initially mentioned in the editorial section written by Chris Anderson (1985) 

Some things which you may think are slurred comments, but are in fact quite deliberate are a few strange new words scattered round the mag, like 'Shmup', 'aardvark' and 'wimp out'. You'll find a full explanation for all these on the last page of the mag, so don't panic. (p.5)

 As promised, the back of the issue contained a definition of “Shmup”

A Zzap-coined term to replace the long-winded 'shoot-em-up'. Any game involving stacks of blasting and zapping.

 The term Shmup was also used in the review of Drop Zone (UK Gold/Arena Graphics, 1985)[1] written by Julian Rignall in the same issue of ZZap!64.[2] Despite ZZap!64 claiming credit for the invention of the term, it is believed contractions of ‘shoot-em-up’ first appeared in Western arcades around 1978, the same time that Space Invaders (Taito, 1978) was dominating the arcade market.

By 1985 the Shoot-em-up family tree had spawned many new branches and there was much variation within the genre. Within Western culture, there came a need to classify all of these sub-genres and to this day, Shmups has been the term of choice. Contrarily, in Japan the genre is still known as shooters; it would seem peculiar that a Western magazine specializing in computer games would ultimately dub a Japanese-created arcade game genre. It could be argued that the term ‘Shoot-em-up’ is highly representative of the ‘Country and Western’ mentality of Western gamers. The ‘shoot first, ask questions later’ culture of Western movies and related folklore reflects the machismo and bravado-driven behaviours commonly role-played in popular videos games such as Grand Theft Auto III (Rockstar, 2002). Alternatively, the more subdued and detached term of ‘shooters’ or ‘STG’ used by the Japanese gaming population suggests a less ‘personal’ approach to playing these games, with less emphasis placed on the successful extermination of an imagined enemy, and with much less pleasure derived from the final act of execution. A parallel exists in karaoke in Japan, where it is participation and effort that count, whereas Westerners see karaoke as a kind of talent contest, with a single, ultimate winner. In itself this suggestion poses as problematic when attempting to extract the subtleties and nuances that make for such different and distinct interpretations of the same material. The contrasting titles given to these identical games by these two cultures could be construed as highly suggestive of corresponding, yet diverse, underlying societal mentalities.

Although the term shooter is synonymous with a wide variety of games, Shmups constitute a distinct category within the larger shooter family. In many respects, Shmups are also the genre responsible for the development of contemporary shooting genres such as the ‘First Person Shooter’ (FPS). To distinguish Shmups from the larger body of shooters in general, there are a number of rules which one can use to distinguish a Shmup. The following section defines the Shmup genre based on discourse in contemporary user groups.

Defining the Rules

In recent years, Shmups and their genre classification has become a hotly contested topic within the Shmups.com community. As the name implies, Shoot-em-ups are focused on the player destroying overwhelming numbers of enemies, and what distinguishes Shmups from Shoot-em-ups is the way that the player must do this.

Shmups are defined by certain unique elements of game mechanics[3] including aspects of player perspective, the game world, control, objectives and themes. Starting with control, the player takes control of their avatar from a third person perspective. Using the directional controls, the player is able to move freely along X and Y axis of the screen. The Players orientation is fixed to that of the primary scrolling axis (Figure 1).



Figure 1 

The player has no control over the view perspective of the game. The game will scroll automatically along its primary axis of movement at a speed determined by the game, beyond the player’s control. The player observes their craft from a fixed third person perspective, either above or to the side of their ship depending on the type of Shmup.

In most cases, the player’s orientation is fixed so that their craft is facing the primary axis of movement. However the most notable exception to this can be seen in Zero Gunner and Zero Gunner 2, where the player has the ability to control their ships direction without impacting on scroll speed or direction.

Movement of the player’s craft in Shmups is fixed to X and Y movements primarily. Movement along the Z axis if present is nearly always controlled by the game’s pre-determined scrolling. If, however, Z axis movement is controlled by the player it is usually implemented as a button, not as a function of the directional control pad. Aside from directional control, Shmups control schemes must also utilize at least one "shoot" button that controls the player’s primary mode of fire. In terms of multiplayer control, Shmups can only be played co-operatively with a second player. Enemy control is strictly generated by the Shmup program itself without the interaction of a second gamer.


Shmups also incorporate certain gameplay elements related to the successful completion of the game. Specifically, Shmups are primarily score driven and rely on the player’s ability to exploit the given Shmups “play system” to their advantage. The main objective of a Shmup is to progress through the level in a linear fashion, destroying or removing enemy craft from the screen by the use of directional control and a primary fire mode. Destruction of enemy craft results in increases to the players score. Clearing the level also results in the continuation of the game to another level, further allowing good players to increase their score at increasing difficulty levels.

Game AI (Artificial Intelligence)

A major distinguishing feature of Shmups is the inclusion of a game world that lacks real enemy artificial intelligence. For example, the game world often follows pre-determined patterns and dictates the movement of the game player, rather than reacting to the movements of the game player. Certain exceptions to this exist and can be seen mainly in aimed bullets patterns and certain boss attack strategies. More often than not, Shmups rely on pre-defined, static patterns of enemy movements. Therefore, the player’s ability to finish certain Shmups relies mostly on their own ability to remember the movement and placement of enemies throughout the various levels in a Shmup. The only non-static element in Shmups AI is the movement of bullet patterns. Although some bullet patterns remain unchanged, the majority of bullet movement in Shmups is programmed to home in on the player’s ships at various screen co-ordinates. However, this homing is mostly limited to only single co-ordinates and lacks the ability to constantly home in on the player’s craft.

What about games that don't meet all of these criteria?

As with all types of genre classification there are certain borderline cases that need special consideration in the classification process. In cases such as these it is sometimes easier to look at what elements are totally foreign to Shmups to eliminate certain borderline cases.

  • Players cannot have control over Z axis movement.

  • The use of a jump button for movement

  • The inability to move along the X and Y axis freely with the sole use of the directional pad

  • Games where scrolling along the primary axis a) is controlled by the player’s movement, for example In the Hunt and b) scrolls freely along all axes.

  • The player’s primary mode of fire must not move along the Z axis, for example, Space Harrier.

Vertical and Horizontal Shmups

Two commonly used sub categorizations: Vertical Shmups and Horizontal Shmups are further used to define the genre. Both of these sub-categorizations are based on which axis (X or Y) the Shmups background scrolls along. In the former of the two sub categories, Vertical Shmups, the background scrolls from top to bottom along the Y-axis of the screen. Vertical Shmups are played from an above third person perspective as seen below in the screenshot taken from Ikaruga (2001) (Figure 2).[4] The orientation of the player’s craft is also bound to the way in which the background scrolls. For instance, in vertical Shmups, the front of the player’s craft is pointed toward the top of the screen; hence to move forwards (along the Y-axis) the player must push up on the directional controller (Figure 3).


Figure 2 


Figure 3 

In the subcategory of Horizontal Shmups, the background scrolls along the X-Axis of the screen. Horizontal Shmups are played from a side-on third person perspective, similar to looking at a cross-section. In the majority of horizontal Shmups, the background scrolls from right to left and the front of the players craft faces toward the right of the screen as seen in Figure 4,[5] taken from Border Down. Therefore, for the player to move forwards in a horizontal Shmup (along the x-axis), the player must push right on the directional controller (Figure 5).


Figure 4 


Figure 5 

Depending on whether a Shmup is vertical or horizontal, the screen orientation must be adjusted accordingly. For instance, most Vertical Shmups use a screen orientation ratio known as 3:4 (three is to four). This means that either the screen must be orientated on its side (as a normal television is 4:3) or the game plays with large black borders on a regular 4:3 monitor. However, Horizontal Shmups take advantage of regular screen orientation (4:3) (Figure 6).

Figure 6 

As always, exceptions must be made: some Vertical Shmups use a regular 4:3 screen orientation, although a side effect of this is that player’s visibility along the primary scrolling axis is limited. This feature is mostly saved for home console only Vertical Shmups, as most people did not want to turn their televisions on their side just to play one game.

Despite the encompassing nature of the above two sub categories of Shmups, some games in the genre do not completely conform to the above definitions. For example, some early Shmups such as Viewpoint (1992) scrolled isometrically along the screen. More recently, however, a Shmup by the name of Zero Gunner (1996) gave players the ability to rotate their craft variably through a full 360 degrees. Zero Gunner also introduced a variable scroll axis, therefore combining a number of scrolling techniques – vertical, horizontal and diagonal. Zero Gunner is, however, still classified as a non-orthodox Vertical Shmup, as the player observes the game from an over-head third person perspective. Zero Gunner is however still classified a non-orthodox Vertical Shmup as the player observes the game from an over-head third person perspective.

Shmups such as Ikaruga (2001), Radiant Silvergun (1999), R-Type (1987) and Raiden DX (1994) are zeitgeists of the genre; games which are synonymous with the time and mediums for which they were created.  These games are iconic representations of the genre and are testament to how widespread and successful the Shmups genre has been over a prolonged period of time. If Shmups are the constant by which one tests the variables, then the variables therefore need to be identified and tested.

The case study Shmups in the analysis chapter only represent the genre at its height, and subsequently do not cover information that provides a contextual reference for the genre as a whole. Therefore, before moving into the analysis of Period One, a concise overview of the genre’s development will be presented here. This discussion also provides evidence of the importance that familiarity played in the development of the genre. To understand this evolution of gaming, one has to track back through a gaming landscape of nearly 3,500 unique games to expose the genre’s roots. Even the most gaming illiterate reader can immediately make the connection between the above genre definition and one particular zeitgeist game Space Invaders, but can the genre be traced back even further, and can the genre be traced back to its para-gaming roots?

This brief overview of the genre provides essential context for the future analysis. The information presented below is not comparative analysis, but rather an overview of the evolution of the Shmups genre. This section of Shmup development will herein be referred to as ‘Proto-Shmups’, as these particular games, although bearing a resemblance to later Shmups, do not follow all of the prescribed Shmup standardizations as presented in the introduction.

Pre-History of the Shmup Genre the Year of the Invasion

In 1978 only a handful of arcade games had been publicly released. The consumption and development of arcade games remained outside of the public consciousness for the most part, but there was a growing presence in this market. The home console market was in a similar state, although things weren’t as optimistic on the home front. Even after the arcade success of Pong (Atari, 1972), Atari had by no fault of their own set in motion a course of events that would eventually lead to the financial collapse of many companies in 1977. It seemed that the success of Pong in the arcades had created a need in the home console market for the game; a need that too many companies were only too happy to fill. Pong clones flooded the home console market and by 1977 the market place could not sustain all of the companies keen to cash in on Atari’s success. The result was the financial demise of many of these companies.

Although the home video game market was still kept active by such consoles as the Magnavox Odyssey, the technology behind these machines had been superseded by consumers’ expectations - expectations that the more advanced arcade technologies were promoting. With the advent of the microprocessor first used in Gun Fight (1975), game developers began to create more ambitious games. Graphics, sound and game play elements were all to benefit from new technologies. Combined with the consumer dissatisfaction with the home console market, these two elements led to the beginnings of the arcade’s popularity. However, the mainstream assimilation of video games was yet to come.

Throughout 1977, no less than thirty-six digital arcade games had been released in both Japan and North America, and by 1978 that number had grown again to forty-three games, most of which were released by Atari or Midway.[6] By 1979 that number had doubled to no less than 96 games and by 1980, the number of arcade games had nearly doubled again to 167 releases.

From 1978 to 1981, Midway, Atari, Taito, Data East and Nintendo created some of their very first arcade games, and with the rapid growth of the arcade industry came public awareness. Games like Space Invaders (1978) caused currency shortages and legal battles. PacMan (1980) inspired popular music by Buckner and Garcia called “Pac-Man Fever” and Pac Man went on to become the most recognizable arcade game ever created (Lindsey, 2002). However, it was Space Invaders that planted the seed from which the family tree of Shmups grew.


Space Invaders

Although not a Shmup by today’s standards, one of the very first games to initially develop the genre of Shmups is Space Invaders (1978). Space Invaders was first released in 1978 by Taito in Japan, and then later licensed to Midway for release in the United States. The release of Space Invaders in Japan was such a success that it caused a Yen shortage around the country, an event only rectified when the Japanese government quadrupled the production of 100 Yen coins (Bousiges, 2004). Many small grocery stores and markets in Japan got rid of their produce and converted into “Space Invader Parlours” or “Space Invaders Houses” overnight (Bousiges, 2004). The “Thump, Thump, Thump” music of Space Invaders was heard all across Japan as loud speakers belted out the menacing, atonal noise of invading aliens.

Later that same year Space Invaders began its assault on the United States. The game was one of the first to break out of arcades and milk bars and into the consciousness of non-gamers. The effects of the Space Invaders phenomenon was felt so widely and deeply that concerned residents of Mesquite, Texas, took banning the machines to the Supreme Court in order to stop the “illicit machines” from “souring” the minds of their youngsters (Bousiges, 2004).

Space Invaders brought two main technical innovations to the world of video games. Space Invaders was the first game that could save players high scores, and secondly, it was the first game to have a soundtrack, albeit a menacing, atonal aural assault compromising of few notes and mostly noise. Along with Space Invaders’ technical innovation came innovation in the field of game play. Space Invaders lay in place the framework for all vertical Shmups to come by introducing three main-game play criteria:

  • A fixed overhead third person camera perspective (Figure 7)

  • A static player orientation (Figure 8)

  • Directional input schemes that allowed movement along one axis


Another feature of Space Invaders is that it was the first truly addictive single player game experience. Jørgen Kirksæther (Kirksæther, 2004), in a radio interview with Halvard Jakobsen for the Norwegian radio station NRK had the following to say:

It took the Japanese to figure out how to make a satisfying single-player game. The key is that you should never be able to win. The Americans could never have created that game, he says, because the idea of a game that can't be won is inconceivable within the American culture. The Samurai codex of the Japanese, on the other hand, allows for the idea of losing with honour, Jørgen says. After Space Invaders, which was a huge success, both the Americans and the Japanese made and are still making popular, unwinnable games.

Toshihiro Nishikado, creator of Space Invaders states in a BBC documentary “I Love 1978” that he himself can only get to level three of Space Invaders (I Love 1978, 2002).

Figure 7 

Figure 8 

Although these features had appeared in video and arcade games before, the combination of these elements was something new. Space Invaders also brought with it a new theme for video games, probably best surmised in the game’s title and most likely inspired by the large amount of sci-fi films being produced at the time. This theme has carried itself over into countless Shmups, even until this day.


However there is some controversy as to whether Space Invaders was truly an “original” game. Two reputable Internet sources, Zube (2004) and Williams (2004), point out that Space Invaders was heavily influenced by a previous Taito game called Space Monster (1972) (Figure 9).[7] Williams (2004) states that “Taitotronic’s Space Invaders was based on the mechanical game Space Monster, released by Taito Trading Co., in 1972”. Despite this, Space Invaders designer Nishikado refutes these claims. Zube (2004) later stated:


(On the other hand,) Toshihiro Nishikado, the designer of Space Invaders, gave an interview in the November 2001 Electronic Gaming Monthly (EGM) and he makes no mention of the game [Space Monster]. David S. J. Hodgson, who interviewed Mr. Nishikado, states that he was "IN NO WAY" (Hodgson's words) influenced by the game. (para. 4)


Despite this, Nishikado makes two contradictory comments in later interviews. In a BBC documentary about popular culture in 1978 entitled I Love 1978, Nishikado states the following: “The original idea was to create a kind of shooting game with several targets on the screen for the player to shoot. I wanted to have human targets but we saw that might be a bit too violent so we decided to use aliens instead” (I Love 1978, 2002).

Although Nishikado’s reference to creating a “kind of shooting game” is mere speculation when comparing Space Invaders to Space Monsters, an interview in issue three of Retro Gamer Magazine is more concrete. In the interview about the origins of Space Invaders, Nishikado states that “I wanted to create a parlour shooting game…” and when asked about whether he was happy with the title of Space Invaders, he stated that he initially wanted to call the game Space Monster, but a Taito official advised him to change the title.

Figure 9 

Space Invaders to this day is still making money via licensing agreements, which have seen it released on new generation mobile phones worldwide. The Museum of Computing Magazine estimates that by 2003, Space Invaders had made a staggering 500 Million US dollars for Taito, making it one of the highest grossing games of all time (Waddel, 2003).

Although Space Invaders may have been condemned by a Texas right wing Christian group, the game received positive reviews from a 1980 issue of The Christian Science Monitor. The article from this issue, “Aliens in the pizza parlour!” by staff writer Peter Grier (1980), praised the game while at the same time shedding some light on consumption of the game in that year:

It has since become the most successful coin-operated game ever sold in America. The average video game or pinball machine is manufactured for only 90 days before production switches to a new model, but Space Invaders is still being snapped up by amusement arcades and burger joints after 22 months on the assembly line. Even Midway can't quite figure out why it's so popular.


Sometimes we scratch our heads, and go, ‘Why has this continued so long?’ sighs Stan Jarocki, Midway's marketing vice-president. But there's no end in sight. I think it's just a release from tension. No matter what your score is, you'll enjoy it, and want to play it again. (p. 45)


Grier (ibid) also goes on to state that Space Invaders machines in good locations brought in as much as $1000USD for their operators. Space Invaders was revolutionary and although there had been Shoot-em-Ups before it, none had managed to successfully combine the game play elements quite so successfully.

Outside Influences on Space Invaders

Tracing the family tree of Shmup development begins to become difficult when moving further back than 1978. Part of the reason for this is that not many of the analogue gaming devices from this era survived, and unlike digital games, emulation has not been able to preserve them. However, Nishikado does give some insight into the influences behind the creation of Space Invaders.

In Retrogamer magazine (2004) and the BBC documentary series I love 1978 (2002), Nishikado makes reference to a few of the pre-cursory concepts that he wanted for the game that was later to become Space Invaders. Originally, Nishikado wanted to either use Tanks or Humans as the target. As discussed earlier, Taito and Nishikado decided that shooting humans would prove to be too violent, whilst animating the tanks’ approach would require too much expensive hardware.

Ninety-eight digital arcade games pre-date the release of Space Invaders: five of those games have game play elements similar to Space Invaders, and all of them have a military theme.

  • Sea Wolf (Midway, 1976)

Similar Layout to Space Invaders, but enemies did not attack the player; instead the player had to accumulate maximum points within a pre-defined period by shooting enemy ships.

  • Depth Charge (Gremlin, 1977)

The player attacks enemy subs from the top of the screen and although enemies do shoot back, they do not converge on the player’s position.

  • Destroyer (Atari, 1977)

Similar to Depth Charge, but the player has no control over their movement. The player controls the firing of depth charges and the depth at which they explode.

  • Guided Missile (Midway, 1977)

The player fires missile up the screen (Y) and then controls their descent into enemy craft, played against a time limit.

  • M79 Ambush (RamTek, 1977)

Player fires projectiles from base of screen at enemy craft moving along the X axis; the player must accumulate points against the clock.

The seed that was planted by the release of Space Invaders in 1978 grew at a frantic pace, inspiring numerous copies, modifications and hybrid variations on its game play. The combination of new technologies and variation to the already successful Space Invaders recipe developed the first fork in the branches of the Shmup family tree: Vertical and Horizontal Shmups had been born. Space Invaders; however, was not solely responsible for the game play developments that were to follow.

The Proto-Shmup period is a time of massive experimentation and growth within the Shoot-em-up genre. Many developers based their designs on the successful model of Space Invaders and then began to experiment with game play ideas. The period between 1978 and 1983 established the ground rules and principles for the Shmup genre.

The Family Tree

Figure 10, although illustrated in a linear fashion, is the product of the back tracing of the Shmup genre to identify games that established key genre elements before others.


Figure 10 

Figure 10 shows the perceived development of the Proto-Shmup genre by looking at elements of player interactivity within the game world. The freedom of movement along various spatial axes and other control interfaces is fundamental. The following examination of Proto-Shmups delves into this initial family tree to try to explain why certain games have expanded upon others and ultimately, why games like Mission X and Battle of Atlantis developed into a game play framework for Shmups.

Sky Raider

Following just after the 1978 release of Space Invaders, Atari released a little known game called Sky Raider (1978). Sky Raider was not just another clone of Space Invaders but a new style of Shoot-em-up game. Unlike Space Invaders, Sky Raider put the player at the helm of a bomber aircraft, in charge of the deployment of its bombs. Also unlike Space Invaders, the player was not represented by an on screen entity (such as the missile base used to represent the player in Space Invaders; instead, the player had control over a moving cross hair on screen. As the player was not represented by an on-screen avatar, the player was therefore unable to be damaged by the enemy. The game mechanics represented this fact accordingly, as the player was put up against a time limit in which to achieve their best score rather than subject to enemy attacks.

Even though Sky Raider does not appear to represent modern day Shmups, it did contribute two very important factors towards what we know today as Shmups. Firstly, Sky Raider was the first game to use a constantly scrolling background (Bousiges, 2004). The games’ arcade flyer expands on this fact more: “A unique new engineering concept presents the player with a birds-eye view of continuously moving video terrain passing bellow. The simulation of flight is realistic and irresistible!” (Sky Raider, 1978).

Sky Raider was intended to be a realistic flight simulator, although the player only had control over dropping bombs on enemy targets. To aid this sense of “realism”, Atari choose not to use the traditional directional pad and buttons configuration of other arcade games of the time. Instead, Atari used a traditional aircraft flight yoke for the input device. Sky Raider also provided another key game play feature to vertically scrolling Shmups created thereafter. The weapon system used in Sky Raider accounted for the targeting of ground objects through the use of a separate weapon aimed via the use of a cross hair. Sky Raider, like Space Invaders, only offered the player movement along a single axis; however, the velocity of the player (represented via background scroll speed), could be controlled by either pulling back or pushing forward on the flight yoke (Figure 11).[8]

Figure 11 

Phantom II, Midway and the 8080

Ironically, one of the most important developments in Vertical Shmups is developed on the very same hardware as the initial innovator, Space Invaders. Based on the same 8080 processor design as Space Invaders, Phantom II took the military themes of the Pre-Proto Shmups and placed them into one of the very first instances of continuous scrolling, direct fire shooters.

HeliFire, Radar Scope and Nintendo

Six months before Williams released what was to be one of the most influential Shmups, Defender (1980), Nintendo released a game that is the stepping-stone between Space Invaders and Defender. HeliFire (1980) was a combination of Space Invaders’ styled game play, coupled with the first ever vertically scrolling game play elements. In HeliFire, the player was put in charge of a submerged submarine. Enemy planes would fly vertically above the player and attempt to drop bombs on them. At the same time, the player had to shoot projectiles from their submarine at the above enemy planes. (Figure 12)[9]

Figure 12 

One of the most striking features of HeliFire is that the game scrolls from right to left, as opposed to the large majority of vertical Shmups that scroll in the opposite direction. HeliFire also incorporated the same fixed scroll speed as Sky Raider and Astro Fighter. Even though the game scrolled along a horizontal axis, the screen orientation was still set to vertical, demonstrating the influence that Space Invaders had on all Shmups of the era.[10]

HeliFire was the third last Shmup that Nintendo created for the arcade. Nintendo’s last ever arcade Shmup, Space Firebird (1980) was released just five months after HeliFire in November. Previous to HeliFire, Nintendo had created only three arcade games, two of which were Space Invaders clones: Space Launcher (1979) (Figure 13)[11] and Space Fever (1979). Nintendo’s change in direction can be squarely attributed to the release of Shigeru Miyamoto’s Donkey Kong (1981).

Figure 13 

Before the release of Nintendo’s famous Donkey Kong, Nintendo manufactured another Space Invader styled Shmup by the name of Radar Scope (1980). Radar Scope, although based on the same style of play mechanic as Space Invaders, used a different visual perspective and game play features. The view that the player had of the game was still a third person overhead, however, the player viewed the game from an overhead third person, depth perspective (a technique that creates visual depth by use of size bias at the bottom and top of screen) (Figure 14).[12] The game’s own flier describes this technique as “3D Vectors”. This type of visualization was not seen again in a game until the release of Silpheed in 1993.

Figure 14 

Radar Scope was the first Shmup to allow the player to fire off multiple projectiles at once. Before this, the player could only shoot one projectile at a time and was only allowed to shoot again, once the previous projectile had left the screen or made contact with a target. Radar Scope was also unique because instead of issuing the player with a number of lives, it used a damage system whereby the player was not affected by the one–hit, one–kill’ system that many similar games had used (Figure 14).[13] Despite the game’s advancements on the already established Space Invaders formula, it sold poorly, even though Nintendo star Shigeru Miyamoto (Mario Bros., Donkey Kong) worked on the game. Of the three thousand Radar Scope machines produced, around two thousand of them were converted into Donkey Kong Machines (Bousiges, 2004).


In 1980, the introduction of Defender (1980) would literally turn the embryonic genre of Shmups on its side. Defender was the first ever Shmup to scroll horizontally and to also have its screen orientation set to horizontal (unlike HeliFire). The player was put in control of a ship called the “Defender” and assigned the task of protecting the earth citizens from alien abduction. When asked what ideas led to the birth of Defender in the September 1982 issue of Joystick Magazine (as cited in RecRoom Amuesements, n.d.), game creator Eugene Jarvis said:

Steve Richie and myself were sitting in a room toying with concepts and game ideas. Steve said: 'Wouldn't it be neat if you were flying over a planet on a screen.' And we tried to figure out what do with it. You could be flying over the planet, you could go up and down in any direction you want…I eventually said: 'We can't do that yet, but what we can do is fly left and right and so on. (para. 8)

The game is unique even by today’s standards as the player could both scroll from left to right as well as an obscure right to left. This innovation however came at the cost of playability. For the time Defender used a record of five buttons and a directional pad for its control. Bousiges, (2004) states that “Due to the intimidating controls, no one played the game and there were even rumours saying Pac Man and Defender would bomb and Rally-X would be the next hit [from Atari]”.

Defender brought with it much innovation, particularly in graphics and game play. Defender was the first game to utilize a ‘bomb escape’ technique, where the player has the ability to clear the screen of both enemies and enemy projectiles through the use of a single button. This game play feature gives the player an ‘escape’ when things get a bit tough.

Defender also utilized a primitive form of artificial intelligence that allowed game play events to occur outside the player’s field of view. These events, such as enemy movements and placements, were depicted by the use of “radar”. At the centre of the radar screen was what the player could see at their current position. To the left and right of this centre position where events that were occurring outside of the player’s field of view; this technique was later attempted in Cosmic Adventure (1981).

Defender, along with Space Invaders created a spirit of competition within those hardcore elements of the gaming public. This spirit of competition also made news in Time Magazine in 1980. The article “Games that People Play” featured a gamer by the name of Steve Jurasek who played Defender non-stop for 16 hours on one credit.

After the release of Defender, Eugene Jarvis broke from Williams to form his own company, Vid kidz. In the wake of Jarvis’ absence, Williams became desperate for a new game and later took Vid kidz under his wing as official second party developers, commissioning the development of a follow-up to Defender. Even though Jarvis was opposed the idea of creating sequels, Larry DeMar (co-founder of Vid kidz) talked Jarvis into creating an enhanced “Defender” game. The result of this was a game called Star Gate (1981). Jarvis was determined to make the game that Defender could have been. In an interview from Halycon Days, (Hague, 2002) he stated the following:

It couldn't be just a regular cosmetic con-job, but a really cool enhancement. We got real excited about tweaking the code and programming gobs of new and cool enemies and getting better real-time performance so more stuff could be packed on screen without blowing the silky smooth sixty frames-per-second performance. The "Stargate" warping feature was just icing on the cake. (para. 14)

The result of this was a more hectic game, only aided by the fact that a record six buttons as well as a directional pad now controlled the game. The game was completed at a furious pace in order to meet Williams’ deadline. The game was completed in four months and was programmed in split shifts. Jarvis, (as cited in Hague, 2002) states:

....on a dual 8" floppy drive 1MHZ 6809 Motorola Exorcisor development system. Since PCs were very expensive in those days--about $30,000--we worked on one system in Larry's spare bedroom. I programmed the system in the day, and he worked at night. And in four months it was done. (para. 15)

The release of Defender in 1980 caused Williams’ nine months gross sales to increase from $83USD million in 1980 to $126USD million in 1981. Williams moved to capitalize on the success of Defender and hence decided to build a new facility in Gur-nee, which was capable of producing 600 to 700 Defender units a day.

Scramble (Konami, 1981)

Scramble (1981) was only the sixth ever arcade game to be released by Japanese company Konami. The game was released in February 1981 in Japan and was later licensed to Stern for an American release in May of the same year. Due to Scramble’s similarities to Defender, it became known as the poor man’s Defender as it didn’t have the same graphical flare as the later title. However, graphics alone do not make a game. With the creation of Defender, a new genre of games had been created - the horizontally scrolling Shmup. The impact that Defender had on the arcade industry wasn’t fully apparent until the following year, 1981. Here, nine more vertically scrolling Shmups were released in the arcade alone, making 1981 a very popular year for Shmups of the vertical kind.

Scramble was an influential game for the time, so much so that other similar games were dubbed ‘scramble clones’, much in the same way as the term or genre ’space invader clones’ was dubbed. This situation was compounded by the fact that Scramble used no encryption so many different, hacked versions can be found (Scramble, 2004). Despite the impact that Defender had on the creation of vertically scrolling Shmups, it still is not representative of the genre today from a game play perspective. However, 1981 introduced nine new vertically scrolling Shmups, each bringing with them variations of the game play “recipe” that Defender had introduced.

Although Scramble may look similar to Defender, the two games are very different in game play. Unlike Defender, Scramble used a fixed scroll speed hence the player could not speed up or slow down their velocity. Scramble also allowed the player to move freely along each axis using the directional pad (Y limited to 50%). Additionally, unlike Defender all movement was controlled via the directional pad.

Scramble also introduced multiple weapon systems that accounted for the targeting of both ground and air targets with separate weapons (Figure 15).[14] Bombs were utilized for the targeting of ground targets and, like Sky Raider, the player had to account for their velocity by triggering the bomb some time before they were directly above their target. A laser gun was used for sky targets; however, it could also be used on ground targets if the player were at the exact same horizontal level as the target.

Figure 15 

Scramble was the first game to use a fuel system. The fuel system acted in a similar fashion to a game timer, a technique previously used in Sky Raider. As the player progressed through the level they depleted their fuel source (represented by a gauge at the bottom of the screen). Once the player’s fuel had fully depleted, their craft was destroyed. The only way for the player to replenish their fuel supply was to use their bomb to hit “fuel” tanks on the ground (Figure 16).[15]

Figure 16 

The only other Shmup before Scramble to use land objects in the foreground of the game had been Defender. However, in Defender the player could not collide with the land objects and hence it did not affect the game play and was merely aesthetics. Scramble took this concept further by introducing collision detection for these land object such as hill, tunnels etc in the games foreground. This factor gave the game designers the ability to generate levels where pilot error could be critical. Later levels in the game exploited this factor also by creating tight, narrow passages where the player’s progress was hindered by the vast swarms of enemies that filled these tight caverns, a major characteristic of modern day vertical Shmups (Figure 17).[16]

Figure 17 

The game play of Scramble was simple and straightforward. The player was given the task of breaking though the enemy’s “scramble system” (as quoted on the title screen). The game consisted of five different levels, each more challenging than the previous. The first level takes place in/over mountainous terrain where the player must avoid running into the ground whilst bombing enemy ground positions. This section then seamlessly moves onto the next level, which takes place in a tight cavern. The player then exits the cavern and has to dodge wave after wave of indestructible fireballs before moving onto the fourth level, which takes place over a large city. The city level then gives way into tight “machine” tunnels where the player must be vigilant in order to progress through them. The sixth and final level of the game is where the player must bomb the enemy base, which is hidden in a crevice out of range of the player’s normal weapon. Once the player has completed the game it then returns to the beginning and repeats the process, albeit at a greater difficulty level.

Two more vertically scrolling Shmups were released on the same arcade hardware as Scramble: Battle of Atlantis (1981) and 800 Fathoms (1981). Both Battle of Atlantis and 800 Fathoms are very similar in appearance and game play to Scramble, however the most striking feature of the two former titles is that both games put the player in charge of a submarine rather than a space ship. Battle of Atlantis further built upon the free-moving nature of Scramble by allowing the player to move 20% farther along the X-axis, thus giving the allowing the player to move their ship nearly to the edge of the screen. Scramble also had a quasi sequel, which was released the following month in March. Super Cobra (1981) used the same game play as Scramble but instead of the player controlling a space ship, they played as a helicopter. Super Cobra further expanded upon the foreground obstacles created by Scramble. Super Cobra also feature eleven levels as opposed to the six used in Scramble.

Universal: Cosmic Avenger and the “Cosmic Series”

The creation of a new genre of shooter also prompted existing game franchises to adapt to the new style of game play that Defender and HeliFire had created. One such game franchise was Universal’s Cosmic Guerrilla (1979) otherwise known as the ‘Cosmic Series’ entailing four sequels, Cosmic Alien (1980), Devil Zone (1980), Zero Hour (1980) and Cosmic Avenger (1981).

Universal’s first entrance into the arcade game market was in July 1979 with the release of Cosmic Monsters (1979), a pre-cursor to the Cosmic series. Cosmic Monsters offered no real innovation to the proven Space Invaders style of game play and was mainly a graphical update of the original (Figure 18).[17] As the marketplace began to be flooded with Space Invaders clones, Universal needed something to set themselves apart, but still stick with the highly successful Space Invaders game play formula.

Figure 18 

Later that same year in November, Universal released their next game, Cosmic Guerrilla. Cosmic Guerrilla used the Space Invaders game play model but incorporated a new set of objectives for the gamer. Instead of the player guarding his or her own position from incoming enemies, Cosmic Guerrilla tried something different. The objective of the game was to shoot any enemy craft that attempted to reach the middle of the screen whilst dodging enemy fire that rained down from above onto the player’s position (Figure 19).[18] Located in the centre of the screen were a number of friendly craft that the enemy attempted to take. To make matters more difficult, there were two rows of enemies on each side of the screen. The player could only shoot at these enemies once they began to move towards the centre of the screen. If an enemy ship managed to take a friendly craft from the centre of the screen, the player only had a limited amount of time in which to destroy the enemy craft before the friendly craft was lost. The game finishes once there are no more enemy craft left in the centre of the screen, or when the player’s missile base has been destroyed by enemy fire.


Figure 19 

Cosmic Guerrilla, despite its innovation, had not been as successful as Universal would have hoped. In an attempt to increase revenue, Universal went back to basics and created another game in the style of Space Invaders, hence disposing of the Cosmic Guerrilla game play recipe. The result of this was the release of Cosmic Alien in January of 1980. Cosmic Alien (Figure 20)[19] was a blend of classic Space Invaders game play combined with updated graphics, a scrolling star field background and more difficult enemy attack patterns that would later be the basis for Nintendo’s Radar Scope released in November of that year.

Figure 20 

Universal decided to explore the game play of Cosmic Alien further by releasing a more ambitious update to the series later that year. Devil Zone (1980) was the result of more than eleven months worth of work developing the Cosmic Alien game play further. However, Nintendo had already beaten Universal to the punch by releasing Radar Scope (Figure 21)[20] just one month before the release of Devil Zone (Figure 22).[21] The two games played and looked nearly identical and ironically both sold very poorly.


Figure 21 

Figure 22 

Devil Zone used a more advanced set of enemy attack patterns than Radar Scope, allowing for three or more enemy craft to be performing attack manoeuvres on screen at once. The same style of Space Invaders game play was retained in both games and both featured the use of depth bias techniques in the graphics department. Devil Zone did however have one very innovative feature: as well as keeping tabs of the players score, it also used a ranking system that rated the player’s ability on an ‘A, B, C’ system, a first for the time.

Before the release of Devil Zone, Universal also began working on another project based on the Cosmic series: Zero Hour was Universal’s next game in the cosmic series and was released just one month after Devil Zone. Zero Hour was a combination of many game play elements from both games in the Cosmic series as well as other successful Shmups of the time. This combination resulted in what can be seen as the first Orthodox Vertical Shmup (Figure 23).[22]

Figure 23 

Zero Hour was the first vertical Shmup to allow movement of the player’s craft along both the X and Y-axis. Even though Sky Raider had allowed for this freedom of movement nearly two years earlier, Sky Raider did not represent the embodiment of the player on screen. Influences from other earlier “Cosmic” games is present in Zero Hour, namely in the use of a Depth Bias field of play and enemy attack patterns.

The Zilog Z80 processor, the same CPU that had been used in the Scramble hardware, powered Zero Hour. As a result, the programmers were able to combine many graphical and game play innovations into Zero Hour that were previously impossible. The first of these innovations was the animations used to depict the players craft pitching left and right. The next technological innovation came with the introduction of using many on-screen sprites. This was an important hallmark of Zero Hour as during the start of the first level the player encountered asteroids that he or she could blast into smaller pieces in the same way as Asteroids (1979).

Zero Hour is a very fast paced Shmup even by today’s standards. Enemy projectiles move towards the player at an astonishing rate. This is made harder by the fact that the Zero Hour controls are sluggish at best. Zero Hour was also one of the first games to use “levels”. These levels were called screens and increased in difficulty as the player progressed through the game. At the end of each screen, the player had the ability to use the directional controls to land their craft for additional bonus points. A star in the lower right hand of the screen was displayed for each successfully completed screen. Konami later developed the concept of screens further by introducing games with more screens or “levels” in 1982 with the release of Scramble.

No doubt influenced by the release of Scramble in February of 1981, Universal once again set out to recreate their cosmic franchise in the image of others. The last game to be released in the Cosmic series was Cosmic Avenger (Figure 24).[23] Instead of sticking with the vertical orientation that they had pioneered in Zero Hour, Universal chose to follow in the footsteps of Konami, by releasing their first constantly scrolling Horizontal Shmup. However as Universal had done in the past, they attempted to modify existing game play models by adding their own unique twist on the game play.

Figure 24 

Influenced by previous games such as Defender and Scramble, Cosmic Avenger attempted to incorporate some of the features from each of these games to make a new game that would set them apart. Cosmic Avenger used two main aspects derived from Defenders game play: the ability to increase the player’s velocity, and the use of radar that could alert the player to enemy movements outside of their normal field of view. The player could also acquire enemy smart bombs that destroy all enemies on screen, similar to the smart bombs used in Defender.

As Cosmic Avenger is basically a Scramble clone, many of the features seen within Scramble can be seen in the use of the player’s weapon system, which consists of a laser gun as well as bombs for attacking ground based targets. Comic Avenger also features a linear level progression similar to Scramble. The first level sees the player in a futuristic city setting not too dissimilar to that seen within Scramble. The third level is very similar to the cavern level in Scramble, but with one key difference: the player’s craft is submerged underwater. Although this element sounds new it had actually been the focus of three other vertical Shmups released the same year: all of which were Scramble clones (800 Fathoms, Funky Fish (1981) and Battle of Atlantis). After this third level the game then repeated at a harder difficulty level.

The Cosmic series innovation came via the adaptation of elements of other successful Shmups of the era. Although not a truly innovative approach to game design, Universal did manage to use it to their advantage and in the process helped to father a new genre of video games. Arguably, Universal was the “emulsifier” of gameplay techniques and was a necessary step in the development of orthodox Shmups. Universal’s last arcade game was release in 1985. Indoor Soccer (1985) was to be the company’s last game ever before they left the arcade market for good. One of their more recognizable franchises, Mr. Do (1982) was later revived by Visco in the form of Neo Mr. Do (1997) for the Neo Geo. In their time, Universal released twenty-three different arcade games.

Proto-Shmups created the Shmup genre as we know it today by copying the success of Space Invaders. Apart from Sky Raider, no Proto Shmup is truly original, and all owe their existence to Space Invaders. Game play development of the Shmup genre during this period was slow as developers were unwilling to entirely ditch the Space Invaders formula for fear of losing money in the Space Invader­ hungry market place.


Closing Thoughts: Reflecting on Research Done a Decade Ago

Since doing this research there have been great in-roads made to defining a clear vocabulary and approach for understanding games. Although playing 3,500 arcade games sounds like something fun, it took around 4 years to get through all of them, averaging around 16 games per week. A vast majority of these games where different localizations, clones or minor variations however it was s significant task. This issue that I always faced is that I was classifying games based on what mechanics they introduced. My database initially had about 20 fields used to indicate different mechanics such as chaining, movement types etc. Once a new mechanic was discovered, a new field needed to be added to the database, causing a need to go back through most of the games that I had already played to make sure I hadn't missed it in the analysis.

Although Ludology was becoming popular at the time, it seemed that most of the papers on Ludology where squabbling about the legitimacy of the field rather than applying the methodology. Luckily, things have changed and thanks to the work of Koster, Swink & Schell (Among many others) we now have a much more consistent frame of reference to understand game mechanics, but is that enough?

Moving beyond mechanical analysis, I can't help but favor the use of game research models similar to the "ethno musicological” approach whereby we become part of the phenomenon we are trying to research. I have to admit that my own personal investment in the medium (arcade games) was essential to constructing this piece. What became clear during this research was that innovation could not be traced simply by reverse engineering game mechanics – much of the lineage needed to be understood through a broader cultural lens. The controversy surrounding Space Invaders is a great example of this. Had I only traced mechanics, I would not have discovered the importance of games like M79 Ambush and Depthcharge in shaping a seemingly distant and unrelated genre of games. 

To close, I was shocked about how quickly these cultural artifacts diminsih into the ether. Many of the very early games that I had to find where next to impossible to locate. I am greatly thankful for the hardwork of the MAME team and the various dumping teams around the world. This is indeed a very grey area in terms of copyright however without their work we would have already lost many of these important artifacts which have had a lasting impact on the eco-system of games. It is great to see many people around the world taking an active interest in preserving this history but unfortunatly for many of these games they are already lost.


[1] As there is no standardized referencing system for video and computer games, this thesis will use publisher and year information to differentiate different versions of the software. These software references will not be found in the bibliography, other than those Shmups which form the case studies.

[2] http://www.zzap64.co.uk/zzap3/dropzone.html

[3] Throughout this study, game mechanics refers to the types of rules and systems that a particular game uses. This is used as an alternative to the term more commonly known term, “gameplay”.

[4] Figure 2. Ikaruga. Reprinted from [Online] Gamespot. (2003) (Available) www.gamespot.com Copyright 2000 by Treasure Limited. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[5] Figure 4. Border Down. Reprinted from [Online] G.Rev Limited. (2003) (Available) http://www.grev.co.jp/ Copyright 2003 by G.Rev Limited. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[6] Statistics gathered from an empirical analysis of MAME v0.98

[7] Figure 9. Space Monster flyer. Adapted from Space Monster Flyer. Copyright by Taito, 1972. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[8]Figure 11. Sky Raider flyer. Adapted from Sky Raider flyer. Copyright by Atari, 1978. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[9] Figure 12. Helifire.Adapted from Helifire. Copyright by Nintendo, 1980. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[10] As the majority of arcade cabinets came with vertical monitors as opposed to tradition 4:3 aspect ratios.

[11]Figure 13. Space Launcher flyer. Adapted from Space Launcher flyer. Copyright by Nintendo, 1979. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[12]Figure 14. Radar Scope. Adapted from Radar Scope. Copyright by Nintendo, 1980. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[13] Figure 14. Radar Scope. Adapted from Radar Scope. Copyright by Nintendo, 1980. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[14]Figure 15. Scramble. Adapted from Scramble. Copyright by Konami, 1981. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[15] Figure 16. Scramble. Adapted from Scramble. Copyright by Konami, 1981. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[16] Figure 17. Scramble. Adapted from Scramble. Copyright by Konami, 1981. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[17] Figure 18. Cosmic Monsters. Adapted from Cosmic Monsters. Copyright by Universal, 1979. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[18] Figure 19. Cosmic Guerilla. Adapted from Cosmic Guerilla. Copyright by Universal, 1979. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[19] Figure 20. Cosmic Alien. Adapted from Cosmic Alien. Copyright by Universal, 1980. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[20] Figure 21. Radar Scope. Adapted from Radar Scope. Copyright by Nintendo, 1980. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[21] Figure 22. Devil Zone. Adapted from Devil Zone. Copyright by Universal, 1980. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[22] Figure 23. Devil Zone. Adapted from Devil Zone. Copyright by Universal, 1980. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.

[23] Figure 24. Cosmic Avenger. Adapted from Cosmic Avenger. Copyright by Universal, 1971. Reprinted under the terms of “fair dealing” in the Australian Copyright Act, 1968, section 40.



Bousiges. (2004). "History.dat". Official MAME History File.

Grier, P. (1980, 6-June). Aliens in the Pizza Parlour. The Christian Science Monitor, pp. 45-46.

I Love 1978. (2002). I Love 1978. Retrieved 2005 16-May from http://retrogamer.merseyworld.com/ilove78.htm

Kirksæther, J. (2004). Documentary on Video Games. Retrieved 2005 16-May from http://huminf.uib.no/~jill/archives/games/documentary_on_computer_games.html

Lindsey, C. (2002). "History.dat". MAMES Official History File. (Bousiges, Ed.)

Retro Gamer Magazine. (2004, 15-April). Retro Gamer Magazine.

Sky Raider. (1978). Sky Raider Flyer. Retrieved 2004 Retreived 18-September from TAFA: http://www.arcadeflyers.com/index.php?page=flyerdb&subpage=flyer&id=995&image=2

Waddel, A. (2003). History of Space Invaders. Museum of Computing Magzine, p. 7.

Williams, K. (2004). Arcade Fantastic. Retrieved 2005 Retreived 17-February from Classic Gaming: http://www.classicgaming.com/features/articles/arcadefantastic/

Zube. (2004). Errata for Chris Crawford on Game Design. Retrieved 2005 Retreived 17-February from http://www.cs.colostate.edu/~dzubera/crawford.txt


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Luke McMillan


Dr Luke McMillan is a senior lecturer of games design who specializes in rational design approaches and design research. Luke has worked for TwoFour54 Tadreeb in conjunction with Ubisoft and Qantm College to develop and lecture game design curriculum at undergraduate and postgraduate levels. Luke is a specialist in the field of arcade gaming and has recently finished a PhD which examines the role of nostalgia in regards to game design and development approaches.

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