So apparently "Loose" wasn't the theme, the lead was simply saying that the theme was being let loose and being posted. I didn't get to it til after 6 (over an hour after the competition began), but I've got my idea down now (about 35 mins later)
Theme: "1 Hit Point"
The competition actually has two themes "1 Hit Point" and "Golden Gun". Technically the two are very similar; the golden gun is infamous from James Bond, and in Goldeneye, the Golden Gun would kill any (bosses even? Dunno) with one hit, thus technically acting as if they had 1 Hit Point.
I am skipping the gun because I don't really like the idea of shooting one another, particularly with the violence in video games issue heating up so badly!
You play as a ghost, making your way back to the realm of the living. Between you and the exit, though, are 50 floors of terror. You must make your way through each, finding treasure, collecting money and treasure, finding bonuses and the seal on each floor that will allow you to ascend one floor higher.
Why 1 Hit Point? Because, as a dead being, a ghost has negative hit points, and is "passed out" at zero. If you can get through all 50 floors, you'll become a living being once more, with 1 Hit Point (barely alive, but ALIVE!).
Each floor is an 8x8 grid , with every square shrouded in shadow except for the one you start in. As you take a step, you find out what's in the new space... If it's a treasure, money or a story page (note: story pages probably won't make their way into the game in 48 hours), you simply collect it. Seals allow you to travel to the next floor, bonuses let you play a little bonus game of some sort, and enemies begin a battle.
Bonuses: Bonuses are little bonus games (note: maybe just one in such a short amount of time). You get extra treasure or money from them!
Treasures: Equipment can be bought at stores at any moment in the game (ghosts can travel anywhere, since they're ghosts and all, it's just the seals that keep them away from living again), but they can also be found! Equipment includes sheets (armor), weapons and artifacts that do special things (reveal x random squares, automatically jump to the next floor, etc)
Story Pages: Who, or what, are you? Why do you want to go back to the land of the living so badly? How did you die? What is this place? You'll find out!
Battle: Ghosts are fine and dandy, happy with one another, as long as they don't try to escape... But these 50 floors are guarded by all sorts of enemies. They'll be as much of a surprise to you as they are to me at this stage, but they'll be there! I'm not quite sure how battles will be handled yet, it's the one thing I haven't really figured out... But it's not even an hour in for me yet, I'll come up with something :)