Muncher

Munchers are a species of immobile Nipper Plants that grow out of the ground instead of from spores, possibly meaning that they are closer relatives of the Piranha Plant than the Nipper Plant. They first appeared in Super Mario Bros. 3 and later appeared in Super Mario World. Unlike their white cousins, Muncher Plants come in either red, blue, or black, depending on the location. They are almost invulnerable.

Acting much like spikes would, touching a Muncher results in instant death. However, both the Kuribo's Shoe and any Yoshi can walk on them without harm. In a couple levels, they spring from thin pipes. The only way to cross a patch of Munchers is by acquiring a Starman or by carefully Jumping to the gaps between Muncher patches.

They also appear in Wario Land, again black, and again indestructible.

Munchers can become frozen if hit with an Ice Block. Frozen Munchers can be identified by the black ice block in which they are encased (in contrast to yellow ice blocks, which hold coins). They are harmless when frozen and act like platforms, but if one thaws a Muncher out with a fireball, the Muncher will become active again. If Mario hits a P-Switch, then thaws a frozen Muncher in an ice block, the Muncher will turn into a coin, the only way to kill them.