suppermariobroth:

In Super Mario World, it is possible to activate a secret exit in a level after dying under certain circumstances. In Forest of Illusion 3, entering the underground room with the key and keyhole and letting time run out while standing above the keyhole with the key in Yoshi’s mouth will cause Mario and Yoshi to die, but still activate the keyhole as they pass it while falling offscreen. The level then counts as being completed successfully, and no death is counted.
_{Main Blog | Twitter | Patreon | Store | Source: myself, Super Mario World (NA, SNES) in SNES emulator}