I didn't read any rule against it, but in this jam has to be submitted a game with the limitation (the theme is optional) and the other jam asks for a game with the object - optional (the theme is optional too). At the other jam page is written that the game SHOULD contain those things, while in this jam the theme SHOULD be used but the limitation HAS to be used.
As a not native English user, I'm used to more pay attention to terms if you catch my drift.
Feel free to try, rate and comment all my games!🤗