Blockstepper

Blocksteppers are a type of enemy that first appear in Super Mario 3D World. They are red block-shaped creatures with eyes similar to the eyes on Propeller Blocks, -like mouths, and two feet. They also wear brown soldier hats and have wind-up keys on their backs similar to those of Bob-ombs. Their name is a portmanteau of "block", which they resemble, and "lockstep", referring to their synchronized marching formation.

Blocksteppers appear in various levels, where they continually march back and forth along a set path (in autoscroll levels they instead constantly move forwards). They will always travel in groups of two or more, forming lines of several Blocksteppers each. Characters can defeat any Blocksteppers in a group by landing on them with any jump, a Ground Pound or Synchro Ground Pound, the claw, pounce, and claw dive from Cat forms, fireballs from Fire forms, boomerangs from Boomerang forms, the tail attack from Tanooki forms, or coming into contact with one while in the Lucky Cat, Invincible, or White Tanooki forms (as well as the White Cat form in Super Mario 3D World + Bowser's Fury). Defeating any Blockstepper in a group will cause the rest to scatter as they frantically run around, during which period more or all of the group can be defeated. After a few seconds, they will regain composure and angrily chase after any characters nearby in unison.

Blocksteppers reappear in its Nintendo Switch port Super Mario 3D World + Bowser's Fury, behaving identically in the Super Mario 3D World campaign. In the Bowser's Fury campaign, appear, which are identical to normal Blocksteppers in function, but with cat ears and tails. They appear in Pounce Bounce Isle.

Trivia

 * Blocksteppers' chanting while undisturbed is a similar noise to those of Pikmin.