Days of Future Piff
Superstar
There was nothing better than getting that goomba's shoe for the first time.
That shoe made you unmesswithable
Walking on munchers
Stomping out spinies
The only bad thing is that the game took it away after just that one level.
When Nintendo remade Mario 3 on the GBA, they actually brought the shoe back for a couple of the eReader levels.
That shoe was the GOAT powerup.