Master Hand

Master Hand (or as known as The Hand) is a right hand-like entity who acts as the creator of the Super Smash Bros. universe and is also the owner and top collector of the World of Trophies. He is the main antagonist of the Super Smash Bros series. It is assumed that Master Hand is the representation of the child who owns the trophies collected throughout the game. Due to his position as a boss, Master Hand is only playable in the games through hacking (save for Super Smash Bros. Ultimate), but in Melee, a glitch exists that makes him playable. Master Hand's origins are unknown and his and Crazy Hand's purposes are undiscovered. However, Master Hand and Crazy Hand seem to respectively represent creation and destruction. He has been a boss on all Super Smash Bros. games.

In Super Smash Bros. for Nintendo 3DS/Wii U, a huge black-like substance called Swarm emerges from Master Hand when challenging Master Hand and Crazy Hand on 5.1 intensity or higher.

Super Smash Bros.
In Super Smash Bros., Master Hand is the final opponent of the 1P Game. He resides in a level called Master Hand's Residence by fans. He uses his size and shape to his advantage - he slaps, punches and flicks the player around.

Master Hand can't be defeated by normal means; instead, he has 300 HP which must be depleted. Once 0 HP is reached, he explodes into the background and the character is turned back into a toy.

Master Hand also appears in the opening cinematic. He positions inanimate toy versions of two random characters on a table, and, after carefully positioning everything around them, he counts to three on his fingers, snaps his fingers, and changes the table into a stage resembling Princess Peach's Castle.