A Battle of Scale
From SmashWiki, the Super Smash Bros. wiki
A Battle of Scale is a single-player event match in Super Smash Bros. for Wii U. The player controls a tiny Olimar, and must defeat a giant Bowser on Garden of Hope. Due to his high weight and falling speed, further augmented by the giant size given to him, Bowser can be easily juggled and is easy to rack damage on.
This event is unlocked by clearing Fire-Type Frenzy. Completing the event does not unlock any further paths.
Completing the event within 60 seconds on any difficulty awards a Hard Braker Pikmin equipment.