From the Super Mario Wiki
Staying Asheep is a Souvenir found in the game folder of WarioWare: Twisted!. Its name is a pun on "Staying asleep". The game is an extended version of the microgame Falling Asheep. The objective of the game is control the Sheep in the boy's dream bubble, in order to make them jump over a fence. Most of the sheep run at the same speed. Although, some sheep run faster or walk back and forth to confuse the player. Sometimes, sheep with green fur appear in the flock, and generally walk faster and camouflages.