The Adventures of Captain Toad
From the Super Mario Wiki
Ads keep the MarioWiki independent and free :)
The Adventures of Captain Toad are a series of courses introduced in Super Mario 3D World, starring the titular Captain Toad as he goes through puzzle-based areas to obtain Green Stars. In these courses, Captain Toad is the only playable character, and he cannot jump, roll, or use any other move that Mario and his friends can use other than running. His stages also do not feature power-ups, but he can return to his normal size by collecting a Super Mushroom if hit by an enemy. If Captain Toad is defeated, one life is lost. The courses are single player only and can only be played when using the Wii U GamePad. The courses are unlocked from the start, but Enemy Battles or general map environments can make them inaccessible. The courses are available on every odd-numbered world, including World Castle, World Star and World Crown, with the exception of World Flower. The course ends when all of the Green Stars in that course are collected. This concept was later used to develop Captain Toad: Treasure Tracker.