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Designing Interactive Story (PART FIVE)

Greetings. This is part 5 of a 6 part series on Designing Interactive Story. A lot has been written about Interactive story, but very little in way of practical "how do you do it" guides have been made available. Reading these in order is recommended!

Greg Johnson, Blogger

February 15, 2016

14 Min Read

This is part 5 in a 6 part series on Designing Interactive Story. 


One of the big challenges to face in designing an Interactive Story game is player agency.  Earlier we spoke about games being all about what players “do”.  When we’re talking about the role a player plays in an unfolding story, the question becomes “what can I do to affect the story?” 

The basic standard set by most of today’s games involves players moving, shooting, and possibly punching and kicking.  When you stop and think about how you can impact a story based on having access to only these actions, it pretty much comes down to choices of “do I use violence or do I not” , or perhaps “who do I kill?” and “who do I save”.  You can certainly build in higher level choices with this limited agency that result in “who do I align myself with?” or “what quests do I choose to do or not do?”  Still there is a pretty limited set of ways one can affect the world when there is a gun strapped irrevocably to one’s hand.

Admittedly there are other types of agency in games besides simply shooting.  Sneaking and hiding is one example of an agency that isn’t too far off this well trodden path. Many games will make this an optional path to achieving goals. (Thief, Assassin’s Creed, Metal Gear Solid). Probably the most common other type of agency (player action) is contextual action.  Essentially, you come up to some object in the world and you can press your button to open a door, drink from a cup, read a sign, or pick up the key, etc…  Contextual actions are sometime used for interactions with NPCs as well, and sometimes players are given a choice of contextual options from a limited set of actions…  (a) pet the cat,  (b) kick the cat. 

We are undoubtedly shortchanging a few particularly innovative story-games out there that have experimented with player agency.  This question of “what actions can I do, and when” is a core question in any story game.  One might think that if our goal is to mimic the real world, we always want to try and give players access to as many actions as possible.  Actually, there are quite a few reasons why this isn’t feasible, and why sometimes it’s not even desirable.  Here are a few ‘example’ considerations:

  1. We’re limited by our input devices in terms of controlling our avatars

  2. We want to keep our game controls simple and accessible and not bog things down

  3. We want player actions to be clear and unambiguous, and generally physical, since games are all about action

  4. A wider array of player actions means a lot more animation assets for players and NPCs which gets impractical unless you happen to be building procedurally, in which case you have a different set of issues.

  5. With a wide array of player actions, we need to deal with a wide array of responses and a larger set of story consequences (possibly branches).

  6. All player actions need to have an effect on the ‘game-system’  i.e. do they help or hinder the player in achieving their goals.  Many actions make for a much more complex game-system. 

  7. The core console gaming audience loves to kick butt – so if we’re building a game for them and we want it to sell….  Just sayin’.

There are probably other considerations but these are a few.  Basically, it’s not a simple problem.  The answer may not be in giving players a lot of agency,  the way we have in real life.  More likely, it lies in giving them the right agency…. access to good choices at the right time.  The problem with having a small set of fixed actions players can do throughout the game is it severely limits how players can impact the story, especially other characters.   The problem with contextual choices is that players can’t get used to the limited set as part of the fiction, because it’s always changing.  This means that players are continually aware that their choices are arbitrary and limited.  Every time the player wishes they could do something in a game and can’t, it breaks them out of the immersive fantasy.  In contrast, when players have a fixed set of actions, they tend to adapt to the limitations and stop thinking about them after awhile.

Some games have experimented with something called “direct control” where players can essentially puppet their avatar with direct movement. (i.e., as you move your mouse or controller your arm moves).  Direct control seems to offer promise in terms of connecting players more directly to an “ownership” of their actions and allowing them to feel more directly involved but it poses a number of issues and challenges. These are things like:  how do you intuitively map complex actions onto a controller, or what actions add to the experience with direct control, and what actions simply become annoying?  Using direct control in the wrong places, or in the wrong ways, can actually work against your immersion, and make players too aware of the game controls.  (Until Dawn, Octodad, Growing Home, Surgeon Simulator) With the advent of VR, and new infra-red sensing devices, or input devices like rings and haptic gloves, these input-mapping concerns may start to diminish. Perhaps the most intriguing challenge having to do with direct control has to do with NPC characters interpreting player intent, or expressive meaning.  This requires some fairly sophisticated AI.  Even without being “understood” by NPCs in the game, direct control can be a lot of fun.  Some games have used it to great effect in multi-player settings.  (Little Big Planet, MakeOurWay)

A last word on this topic has to do with the shooting itself, or more generally put, the “killing”.  Without getting too deeply into the hot topic of ethics and video-games it’s worth noting that it can be a challenge, from a practical game-play perspective, to come up with primary player activities that don’t involve killing. When one is telling a story through physical action, there are few things easier to communicate, or more dramatic, than simple survival.  Killing is clear and easy to represent with a very limited set of player actions, and easy to make skill-based. That said, there are a ton of great games out there that have found other creative solutions for player action, and their ingenuity should be recognized and applauded.  Unfortunately, a large percentage of the games doing interesting things with Interactive Story have rather dark themes, and bloody subject matter.  This is quite a turn-off to a large population of potential players. (I find I can’t even get through many of these otherwise amazing games). 


It may be a little late to be defining this term, since we’ve been using it left and right already, but perhaps we should take a moment and clearly define what we mean by ‘game structure’.  For that matter, while we’re at it lets define another term we’re tossing about, play-mechanic (or game-mechanic). 

Words are funny things aren’t they?  We toss them around as if they were real solid things, assuming that what we think we mean by them is what other people think as well, because after all, a cat is a cat, isn’t it?  And a game is a game.  In our daily lives it’s generally not productive for us to go around second guessing everything… but the truth behind the curtain is that our brains are playing a continual trick on us, so that we can function on a daily basis.  If you stop to think about it, you’ll see that every word we use is an arbitrary construct; part of our mental model of the Universe we live in.  After all, every thought you have, every perception, and every bit of understanding is nothing more than the machinery of that mental model working away.  At the speed of the electrical wiring in our brains our mental models make causal and associative connections, layering in memories, and emotions, and trying to fit what we see and hear and read, into a bigger picture that makes sense.   When we translate the words we hear or read into ‘meaning’ (reading this sentence, for example), our model is also taking things like context, and intention into account.   All of this happens within the vast neural network of links and associations in our brainputers at super high speeds, with us only really aware of the thought that pops out at the end, as if by magic.

The point here is that words are nothing more than labels we slap onto concepts that have varying degrees of ‘fuzziness’,  by virtue of this myriad of connections to other concepts.  Add to this fuzziness the endless differences between your own mental models, and all those other mental models floating around in all those other brains, and it really is a wonder we manage to communicate at all.  Take a solid, unambiguous word like “cat”, for example.  Is a lion a cat?  Well, sort of, though it’s probably not what your friend meant when they said they were going to adopt a cat.  Now consider words like “game-play” or “art”.  We think we know what we mean when we say “game play” or even “video-game” but these words have an awful lot of fuzz around their boundaries, yet we sling them about left and right assuming our meaning is getting across.  And let’s not even get started on disastrously fuzzy words like “art”.  I’d be surprised if two people’s definitions of this concept line up, yet gamers and non-gamers spend hours debating the question of whether games are “art”, as if they all meant the same thing…. Ok, so it is entertaining.

So, why this little detour into the philosophy of language?  Well it’s really just to point out that the term Game Structure is just an arbitrary construct, as is the term Game Mechanic.  (Come to think of it, I suppose I could have just said that to begin with, but then I wouldn’t have been able to use my “is a lion a cat?” question, and I’ve been wanting to ask that one for a long time now.)

As academic as it may seem to spend time defining our terms, or perhaps even boringly pedantic, there is a very practical and useful application to this.  Knowing what a mechanic is, and knowing what a structure is, or for that matter, a theme, or a story, or a reward system, or whatever, allow you really zero in and think about it with much greater clarity and efficiency.  Fuzzy thinking takes more time.   So let’s get to defining. 



 A ‘game mechanic’ (or ‘game-play mechanic’ or just ‘mechanic’),  is what a player DOES in a game coupled with some aspect that makes this “doing” a challenge, hopefully an enjoyable challenge.  In the first few pages, we talked a little bit about how the goal of a successful game is to empower players though action and choice.  This “doing” is at the heart of what makes a game… a game, and it is a HUGE part of player expectation.  One of the most productive ways to think about game design is by asking the simple question:  “what does the player do, most of the time”.  Surprisingly, even the best designers often forget to ask this question enough.


When coming up with mechanics for a game, or breaking down mechanics for an existing game, one can start by thinking in terms of categories.  There are probably only about 40 or 50 categories of existing game mechanics.  Again, simply put, these are the things players actually “do”.  Here are some examples of these categories:


  • Hand to Hand Fighting

  • Shooting

  • Racing

  • Physical Puzzles

  • Collecting

  • Rhythmic Music Matching

  • Crafting (combining elements)

  • Navigating Conversational Trees

  • Dodging and Jumping

  • Hiding and Sneaking

  • Climbing and Leaping “Parkour” Movement

  • Flying

  • Simple Quick-Button Response

  • Building and Creating


A few specific mechanics might be things like: 

  • Shoot the bird with the slingshot by pulling back and releasing.  Bird moves in an arc based on weight of bird and the distance it was pulled back.  Player attempts to hit and knock over structures to pop the pigs inside. 

  • Move constantly during attacking phase of enemy to avoid getting hit, then strike the enemies vulnerable zone accurately during the enemy’s resting phase. 

  • Attempt to match the musical notes by hitting the correct key within a window of time as shown by the notes passing the bar.


Some simple mechanic might be things like: 

  • Move forward as the terrain becomes visible and try to find the path forward.

  • Move from object to object, hiding from enemy’s searchlight 

  • Press the button within the window of time allowed


A complex mechanic might be something like: 

  • Drive your tank while also turning your turret and using the zoom feature to shoot targets.  Select appropriate shell type for target and attempt to hit enemies in side or rear where armor is weakest, while using terrain for cover and to stay hidden.


Notice that these examples of actions all include the description of the challenge as part of the action.  “Paint a picture” is an activity, it’s not really a game-mechanic, whereas “paint a picture within a 5 second window” comes much closer to being a mechanic.  One thing we didn’t mention, that should also probably be part of our definition of game mechanic, is the idea of being able to evaluate player performance and feedback to them how they did.  “Paint a picture within 5 seconds” still has problems as a mechanic, because it is a difficult thing to judge or give player feedback on.  (as opposed to say, something like connect the dots correctly to form a picture).  This isn’t to say that subjective “creative” activities don’t have a place in games – they certainly do, but in and of themselves they are not game-mechanics. 


One other side note here:  we often hear the term “game play”.  This almost always refers to the collection of mechanics that are found in a single game, coupled with an expectation of these as being ‘fun’.  Gamers and game critics will often talk about game play as ‘the most important thing’ in games.  They may sometimes have a fuzzy concept of what they mean by this, but if you offered them this definition, most would say “yeah, that’s what I meant”.



Now that we’ve described what a game mechanic is, we can distinguish this from what a game structure is.  As we’ve said early on, games can have many mechanics but only one game structure.

To look at a game’s structure we have to step back and look at the game as a whole.  The game structure is, in a sense, the higher-level shape of the game.  It’s the thing that defines the flow of player experience….where do they go, and what do they do, in what order?  Since most games tend to involve movement from one place to another, a game’s structure might be as simple as the map of the game world, with design notes applied to various locations.  Many games are more complex than this however, and it’s often useful to diagram out your game’s structure.  Often there are conditions that players need to meet before they are given access to new parts of the game.  These conditions can be as simple as reaching a location in the game, or it may be collecting certain resources, or making friends with NPC characters, or attaining a certain level, acquiring an item, etc…  Mapping all this out in a flowchart can be of great value.  Among other things, this allows a designer to know exactly where player choice points are in a game.  It’s a bit like writing an outline for a movie.

Game structures for Story-Games generally included some notion of story chapters.  These are the phases of the game where the story context has shifted. Players may sometimes have new goals and new abilities based on the chapter they are in.  In a linear-path game, mapping these story-related changes is very straightforward. In a game that allows for more emergent (or organic) story, plotting the structure is more complex.  Here it becomes a matter of identifying potential story threads and laying out the conditions that need to be met which will change story-related character states and world states.   In the section above titled “Creating a Network of Dependent Gates” we talked a little bit about how some of these conditional networked structures can be built.

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