Kamikaze shell

Kamikaze Koopas are enemies which only appear in Super Mario World and its Game Boy Advance remake Super Mario World: Super Mario Advance 2.

Kamikaze Koopas in Super Mario World are created when a Yellow Beach Koopa enters a shell of any color. Kamikaze Koopas are almost invincible and can't be defeated by stomping. The shell also follows Mario or Luigi in an attempt to hit them. If Yoshi eats a Kamikaze Koopa's shell, he will gain all three abilities from Red Shells, Blue Shells and Yellow Shells, as long as Yoshi keeps the shell in his mouth. To defeat Kamikaze Koopas, the player must eat the shell with Yoshi, Spin Jump on the shell, or make contact with the shell using a Starman power-up.