Tip: If you give a Muncher tile custom graphics, it will still act like a coin when a silver P-switch is active, whether it looks like a coin or not. So make sure to use ExAnimation if there's a silver P-switch in the area.
This patch allows Mario to shoot Yoshi's Fireballs, similar to when you get that special secret item in DW:TLC. However, it has more abilities: first, it has a block flag, so you can restrict the fireball shooting in certain levels with the aid of UberASM; second, but not least, it has a cooldown timer. There's a distinction with the buttons: the X button is responsible for the Yoshi's Fireballs shooting by default.
To be assembled with asar, tested both with LoROM and SA-1. Credit is greatly appreciated.
v1.1 change: Now lets the user swap tilemaps with the Flopping Cheep-Cheeps in order to accommodate the Fireballs' tiles into SP2, making them compatible with every tileset.