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Super Mario 3D World
Charvaarghs make their first appearance in Super Mario 3D World. They appear in only one level, World Castle-7, Simmering Lava Lake where players must make it past them. If a character touches them, a life is lost, regardless of the character's form. Charvaarghs cannot be defeated by any method. They are also the only enemies (including bosses) other than Fuzzy Hordes that can defeat the player in one hit.
However, most Charvaarghs only show up when the player enters a Clear Pipe for aesthetic purposes.
Captain Toad: Treasure Tracker
Charvaarghs return in Captain Toad: Treasure Tracker, no longer used solely for aesthetic effects. They appear in lava stages either coming out of grates which Toad must walk across, or blocking his path where he must run across Dash Panels. They debut in the Rolling Inferno. In this game, they do not instantly defeat the character.
Mario Party 10