Is is possible to make a card game based on slap jack, only with different pictures, and slight variations on the rules? By possible, I mean legal. Does anyone own the rights to Slap Jack?
I know there are already slap jack games on the market, but there are plenty of companies that make their own Old Maid card games, too, so that is not necessarily a reason not to make one.
I doubt anyone owns the rights to slap jack... but depending upon your twist, you'd probably be better off renaming it to fit what you are slapping.
I also don't think any one could claim rights to the "rules" of slap jack... besides, once you change from slapping a jack to slapping a joe, then it doesn't matter.
I don't know what your twist is... but I could see something for the collegiate arena where the deck of cards is primarily made up of things from College A... and the slap card is something dealing with the rivalry school.