Ultra-sun: Their food sources have decreased, and their numbers have declined sharply. Sludge ponds are being built to prevent their extinction.Moon: After recent environmental improvements, this Pokémon is now hardly seen at all. People speculate that it may go extinct at some point.Alpha-sapphire: This Pokémon’s favorite food is anything that is repugnantly filthy. In dirty towns where people think nothing of throwing away litter on the streets, Muk are certain to gather.