Normally, teams are formed when working on Global Game Jam projects. However, for GGJ 2012 I arrived and immediately decided that I would work alone. Not for any malicious reason - I had decided that I wanted to develop my jam game using the impact.js html5 game library, and I didn't want anyone else to be held back by any technical issues that working with a framework for the first time might bring.
The Theme for the Global Game Jame that year was this picture of the Ouroboros. I decided to interpret the theme as "coming back on yourself", but with the knowledge you'd gained before. So I made a simple game with two levels: the overworld and the underworld. To win the game, you had to slay the evil Minotaur in the overworld. However, when the game first starts, your character is very weak, and could be killed easily. When you die, instead of just getting to try the level again, you go into the underworld. In the underworld there are things you can pick up that will increase your strength, speed, health, and jump height when you return to the overworld. You only have a set amount of time to return to the overworld, though. If you run out of time, or are caught by one of the guardians of the underworld, then the game is over for good.
Pathei Mathos can still be played here.