There are a lot of entries in this Ludum Dare which interpreted the theme as You Only Get One Bullet. Technically, No Way Out by Emma Maassen of Kitsune Games is one such, but this game is a short point and click adventure. Rather than giving you one chance to hit a given target, your one bullet is a precious resource that is not to be wasted.

You're safe when the game starts, but in three minutes the zombies outside are going to burst through the door, and if you can't find the way out before panic takes over, you'll get the bad ending, becoming a zombie yourself. While you search for a way out, your pulse audibly increases in pace, and panicked thoughts start to take over the screen. It creates a palpable atmosphere of tension that really makes the game interesting. Even so, the game still sports the snarky sort of humor that pervades most point and click adventures.

I will say that the character pathing is a little flawed. **SPOILER**You have to move down before going into and out of the bathroom, which isn't obvious. It's a pretty big problem, though, because of the limited time and the fact that the good ending cannot be obtained without going into the bathroom.

Disclosure: I am acknowledged in the game's credits under the alias Crowbeak, but I had no part in making the game. I also participate in Ludum Dare, and when the theme was announced Emma and I bounced ideas off of each other. That was the extent of my contribution.

[Play No Way Out]