"Make the player feel like a hero."
That's been one of my game design guidelines, by way of Mark Nau by way of someone at Atari cum Midway whose name I've forgotten. And it's always served me well, but it has its limitations.
Which brings me to the subject of this post: limitations. Taking away limitations and giving the player's avatar more powers is often a good way to make them feel more heroic.
But every power you give the avatar, every limitation you take away, reduces the challenges you can put in front of the player. Take a Spider-Man game, for instance. Spider-Man can climb on walls. Any wall. This is canonical comic stuff here. You make a Spider-Man game, you can't take away his wall-crawling.
But then a whole set of environmental challenges is nixed. (One of the reasons rescuing people and carrying them to safety was a popular challenge in Spider-Man 2 was because you can't wall-crawl and carry someone at the same time: now you actually have to swing across the burning theater floor, etcetera.)
And making the player feel like a hero has been kind of done to death. But it seems like there's a lot of fruit at the other end of the spectrum: can we make a game with one button? (Canabalt) What if we make a game where you can barely control your own muscles? (Qwop)
Enter The Amazing Brok. You play a rock. A rock that can jump. And that's it. The game has two buttons: one button jumps; the other button activates the environment, switching directions of treadmills and activating springs and so forth.
And with these draconian limitations on your character, suddenly this rich field of level design comes out. All sorts of potential puzzles and challenges. Check it out, it's inexpensive and it's on iOS and Android.
I make it sound like there's a continuum between 'be a hero' and 'have interesting challenges': but really, though the two principles exist in tension with each other it is possible to do both at the same time. Canabalt is a good example of that. In games where you've given the avatar a slew of badass powers you can experiment with taking them away in certain sections - Spider-Man carrying civilians, or the randomized powers section of Bioshock - and even in games where you play a fairly unheroic rock, any interesting challenge still makes you the player feel like a hero when you solve it.