0
Glitch
You must have a Blue Yoshi to perform this.
Go to Vanilla Secret 1.
Swallow a Koopa so that your blue Yoshi gets wings. Fly up till you see a trampoline. Eat it. (If Yoshi begins to swallow, spit it out and eat it again.)
Somewhere in the level, you should see a 2-block-wide alcove (if memory serves, it was on the left) formed by a ledge and a pipe.
Spit out the trampoline so it is next to the wall. Then, walk left, into the trampoline. If you did this correctly, you will be pushed into the wall.
The game will behave as if you were crushed, and you will die instantly.