Shredding for Satan: how Metal: Hellsinger designed FPS harmonies in Hell

Metal: Hellsinger is a rhythm FPS where players will blast their way out of Hell as metal music accompanies this daring escape. If the players can time the shooting and combat along to the driving beat of the heavy metal tracks, they’ll be rewarded in a variety of ways, both through gameplay and through a richer experience with the music.

Game Developer spoke with David Goldfarb of The Outsiders, the game’s developers, to talk about how they created incentives for players to shoot their foes to the beat of the music, what thoughts went into designing foes and encounters that would encourage players to shoot them along with the tunes, and how they looked at weapons as “instruments”.

Metal: Hellsinger has players blasting foes to the beat of heavy metal tracks. What interested you in combining rhythm game-like mechanics with an FPS?

I loved rhythm games, knew how to make (and loved) FPSes, and wanted to somehow make an ode to Metal music and the flipside of the Doom coin at the same time. But it all started with the idea of being a demon fighting out of Hell.

What thoughts went into creating the connection between player actions and the music? Into deciding how the player would be rewarded through more intense music and greater destruction?

Many rhythm games (Guitar Hero and Rock Band in particular) reward the player with a higher score for better play, and to some extent even more spectacle (Star Power, etc). After some experimentation, it felt right to have the player's dynamic achievements be rewarded with a power increase of some kind as they played better and better. This went hand in hand with the idea that you would experience the full song when you were performing well, with all the different audio layers present. There was quite a bit of back and forth about the best way to achieve it, so the end product is the result of many, many tests and discussions.

How did this connection between music and combat affect the way you set up enemy encounters? How did it affect the creation of the game's enemies and what they can do?

Encounters had to work in a certain way with the combat that was different from the way you would make a traditional FPS encounter. Because keeping rhythm by interacting (largely shooting) enemies is core to the experience, we needed to have an abundance of targets that stayed more constant, we needed them to appear on-beat in some cases, etc. As for the enemies themselves, some have attacks that are rhythmic as well.

Finally, being hit by an enemy decreases the player's Fury, which affects everything from their score to their experience of the music being more or less intense. So, a lot of the mechanical incentives to experience the game optimally are built into this enemy interaction (on-beat to do better, off-beat or get hit to do worse).

Can you give us an example of your thought process behind a section of a stage or a particular fight? How that tied in with the rhythm shooting mechanic to keep players on beat?

There are no specific examples of this in the level design; it is all primarily game mechanics. There are a few things (the cosmetic background flames, for instance) that reinforce the "on-beat" pulse, or the emissive on enemy characters also being on-beat, but they are peripheral effects. Mostly, we built stages we hoped players would enjoy that allowed for free movement and let the mechanics do the rest.

What ideas went into making hellish firearms for the player to use? Into creating visual designs for guns that felt like they belonged in hell and would fit in well with a game connected to a heavy metal beat?

We had specific rhythm goals for the weapons as "instruments" that primarily informed what we wound up making, but at the same time, there was lore from the story that fed into the weapons as actual objects. So, it sort of developed in parallel, and as with a lot of stuff, we kicked around a few different ideas before settling. The Hellcrow prototype (a sort of boomerang) was a banana in prototype. Many people on the team still miss the banana.

A unique metal soundtrack was composed for the game. How did the nature of the game (hellish landscape, pushing players to increasingly intense music through gameplay) affect the composition of the tracks?

Broadly, the story of the game was the basis for all the lyrics and the levels influenced the pace and feeling more specifically.

How did you design those musical tracks so that they could increase in intensity as the player does well? What went into the design of the audio systems to allow it to keep changing the intensity of the music without sounding discordant?

The composers designed the tracks around our Fury multiplier system, such that there were 5 gradations of instrumentation, and the highest would mean that the vocals came in when the player was performing well. As a player loses or gains Fury in sufficient amounts, the soundtrack adds or subtracts instrumentation layers from the song, and there is some delay and smoothing to keep it from being overly jarring when one goes up or down.

You recently added modding tools that would allow players to battle to various other types of music (like jazz, but...hellish). What drew you to do this? How do different kinds of musical tempos affect the game?

We always wanted people to be able to add their own music and thought it would be a fun thing to add. Higher tempo means everything is faster (enemy firing, player rate of fire, beatmatching), so it can be quite challenging (but fun) to experience a really high BPM song.