One of the biggest challenges of writing for games is that games — unlike novels, movies, or epic poems inscribed in flames upon the walls of the Temple of Steve Jobs — are interactive. Players make game play choices. Those choices affect the game’s story. This takes a chunk of authorial power (is that a thing? it is now) out of your hands and places it, heavy and gleaming, into the hands of the player.
I’ve already discussed the role of scope of your game story. But addressing the element of interactivity makes it worth bringing up scope one more time, just to put a couple finer points on it:
Going too Narrow: Even in a game with the narrowest story-scope, in which the player experiences but a single story, you still have to leave room for interactivity. It’s never truly a single story, but a story with many minor variations. Yes, the story may be the narrow tale of an explorer sneaking into the city of apes, stealing an artifact, and escaping. But one play-through of the game might have the explorer fighting a roomful of apes in the banquet hall, while another has him sneak past the ape banquet via the sewers — if sneaking is a game play choice the player can make.
- Tip: Don’t create a story so narrow that it stops making sense when the player deviates from the expected path.
Going too Broad: Even in the most wide-open sandbox of a game, there must still be borders. There is some point where the story goes so far afield of what the player expects that she can no longer suspend her disbelief.* Yes, you want to make the story broad enough to accommodate whatever craziness the player wants to do, but it still has to hold up in the larger context. In a Star Wars game, for instance, it would be acceptable to allow the player to kill Darth Vader. That’s the sort of thing that might happen in the setting. But it would not be acceptable to let her turn the Empire into a pacifist chain of natural food restaurants. At that point, it wouldn’t be Star Wars anymore.
- Tip: Don’t create a story so broad that it no longer makes sense within the storyworld.
I guess the general rule here is the same as running a tabletop RPG: Expect the players to do the unexpected. Make sure your story is robust enough to not fly apart when the players zig when you expected them to zag. Because as any RPG game master will tell you, players never zag.
*Unless you’re writing for a Saints Row game. Then all bets are off.