What is limited? Apps used (eg IDE, art app, sound app)? Objects in game (player, enemy, etc)? This is extremely vague...
What I mean with that is first you can only have three things of one type in your game (it's like the theme from the GMTK GameJam last year - only one), second you can only use three things to make your game (except that things that I mentioned on the page) for example one thing in reallife for the sound and two programs to make the game (graphics and Engine for example)