Mega Mechakoopa

Mega Mechakoopas (originally known as Big Mechakoopas) are larger variants of Mechakoopas.

Super Smash Bros. for Nintendo 3DS / Wii U
In Super Smash Bros. for Nintendo 3DS / Wii U, the Big Mechakoopa variant of Bowser Jr.'s Mechakoopa move spawns a Big Mechakoopa. Unlike normal Mechakoopas, the Big Mechakoopa can only deal damage upon exploding, and it deals more damage and knockback.

Mario Party 10
The Mega Mechakoopa serves as one of the game's mid-bosses. In its boss minigame Mega Mechakoopa's Swing & Stomp, players must ride up elevators and swing on suspensions hanging from the ceiling to jump on the Mega Mechakoopa's head and deal damage. As its health dwindles, the Mega Mechakoopa moves more erratically and breathes fire to try and catch players off-guard.

Super Mario Maker 2
In Super Mario Maker 2, Mechakoopas can be enlarged with a Super Mushroom. They act the same as their smaller counterparts, right down to using jet engines at night, but cannot be picked up.