Having recently come across some new mutations in cats - to be specific, the one known as the Kangaroo cat - the game idea is for the player to attempt to survive in the wild, using their choice of mutated cat. For examples, I'd suggest cats suffering from dwarfism or polydactyl cats. To survive, you'd need to hunt, defend yourself, stay warm and dry while neither dying or being caught by animal control. Success would be measured by the age that the player survived too in comparison to the average age that feral cats survive too