UnNatural Selection is an amusing tongue-in-cheek battle game in which you play creature cards (ranging from microscopic, animal, historical and mythical) to fight in an arena. Each player is dealt three cards, each card is both creature and modifier. each player except the judge plays one card face down as their creature. Once all the creatures are set out, players take turns placing the remaining cards in their hands face down to alter the abilities of your opponents in funny ways.

Then the players are encouraged to try and sway the player judge (of the round) in their favor, the judge has the final decision of which creature wins the round.

The player whose creatures win a number of rounds based on how many players are in the game wins.