This game should not require too much work; it can be absolutely any game, as long as it's playable.
It can't be a clone of any current game...
It CAN be any game you like.
All it has to have is the picture (see attached) in the background, and it also has to be able to play.
It doesn't have to have heaps of detail or anything, just something to pass time, for example it could be an unlimited wave of zombies, or it could be anything you think of.
The lowest cost will be chosen.