There is no theme. You are on the honor system to only make your game within the allotted time frame.
Make a new game. The jam is not for working on or continuing previous projects.
Jam is ranked. Only people who submit a game can rate games.
Don't use ripped assets. Make your own assets or use stuff you are licensed to use from legit sources. It is perfectly fine to start working on assets before the jam period starts, just don't starting making the game itself until the jam starts.
No hateful (racist, sexist, homophobic, etc etc) or sexually explicit content allowed.