Key

In Super Mario Bros. 2 keys where used to, of course, get into locked doors. Phanto's will always be gaurding keys, so once you have a key, RUN!!! Unless you toss the key, a Phanto will always be chasing you. Keys are usually either in a pipe, or in a room with a massive Phanto mask on the wall. Don't bother plucking every vegetable to find one, they're always in view.