Onigiri is an opponent faced by Mario in Wrecking Crew '98. It is a living ball of rice, more specifically onigiri, which it is named after.
In Wrecking Crew '98
Onigiri is the opponent of Stage A and the first secret opponent fought by Mario. To face Onigiri, Koopa Troopa has to be defeated within four minutes to unlock Stage A. Onigiri itself can be unlocked as a playable character in multiplayer by defeating it.