Crazy Hand (SSBU)
In Classic Mode
Crazy Hand appears as a boss in Classic Mode. For the first time in the entire series, Crazy Hand has the ability to face in either direction (left or right), which he combines with snapping his fingers to teleport around. Also for the first time in the series since Brawl's Boss Battles, Crazy Hand no longer has a stamina HP indicator, now having a health bar akin to bosses from Subspace Emissary and World of Light. This results in Master Hand having a separate health bar as well, meaning that they no longer share the same pool of HP as they did in Smash 4. However, he can now be stunned, which renders him immobile on the ground for about 8 seconds.
The Fighters that are assigned to fight Crazy Hand in Classic Mode are Falco and Ken. Crazy Hand will also fight along with Master Hand if the intensity is 7.0 or above. Ice Climbers, Mewtwo, Chrom, Meta Knight, Pit, Diddy Kong, Ryu, Incineroar, Banjo & Kazooie and Byleth always fight both Master Hand and Crazy Hand.
Like Master Hand, Crazy Hand has received a large variety of new attacks.
In combination with Master Hand
Role in World of Light
Many Crazy Hands appears after Galeem's initial defeat, all of which led by Galeem's dark counterpart, Dharkon. He is fought three times in The Dark Realm, one guarding each of the three pathways into the subareas, and twice more during The Final Battle.
Once the player manages to get the true ending's requirements, Crazy Hand and Master Hand are freed and they help the player by creating a giant rift for the latter to enter and destroy 50 false characters.
Crazy Hand's freedom suggests that, like the fighters, he was captured by Dharkon before the events of World of Light and then cloned into controllable puppets.