Is this in the game? I don't remember it at all. 
It is when yoshi turns into a giant yoshi, by grabbing a RED mushroom. Isyou 20:28, 9 March 2007 (EST)
all the red mushroom are in Wario Blocks. Max2 (talk)
No. But acctually, there all in blocks, and yoshi cant destroy blocks... Isyou 20:30, 9 March 2007 (EST)
They are also in yellow blocks, I think. I've done it. 
3D, SUPER YOSHI BROS.!