Master Hand

Master Hand is one of the main antagonists of the Super Smash Bros. series. The Master Hand is a right-handed, large, disembodied, glove-clad hand. In Super Smash Bros., it has a strange resemblance to Mario's gloves, though they appear less similar in later games.

It has been disputed as to what the Master Hand is; some say it is a god-like being with reality-warping power, while others say it is nothing more than a child with an overactive imagination playing with his toys (This assumption is strengthened by the fact that the hand is shown in a child's room and removing the dolls from a toy chest in the original Super Smash Bros).

Super Smash Bros.
Master Hand first appeared in Super Smash Bros., where it supposedly gave several dolls based on Nintendo characters life and pitted them against each other. After whatever character the player chooses defeats all challengers, they will be transported to the battlefield, the "Final Destination", where they will face off against the sinister appendage. After defeating the being, the player will revert to their original doll state.

Super Smash Bros. Melee
Master Hand reappeared in the sequel to Super Smash Bros., Super Smash Bros. Melee. This game introduced Master Hand's counterpart, Crazy Hand, which is said to embody lust for destruction (the game also says that Master Hand embodies creation). The battle against the Master Hand in this game is nearly identical to the original Super Smash Bros.; after defeating all opposition the player will face Master Hand in Final Destination. The only difference is that Crazy Hand will occasionally appear (only on normal, hard, and very hard difficulty, though); as is in the original, once Master Hand (and sometimes Crazy Hand) is defeated the player will revert into a trophy, appearing among the trophies of others who have defeated the Master Hand. The Master Hand is a much more difficult enemy in Melee because his health increases as the difficulty goes up, and the times can't be turned off in single player anymore (if the timer runs out, then the player automatically loses regardless of health or number of lives).

Super Smash Bros. Brawl
Master Hand is featured in Super Smash Bros. Brawl. In the Subspace Emissary storyline, Master Hand is seen controlled by Taboo. After the strings were severed, Master Hand tries to fight Taboo, but is knocked to the ground by a force field and left unconscious for the rest of the story. He also appears in his usual role as the last enemy faced in Classic Mode. Crazy Hand joins him under the same circumstances as in Melee.

Melee
''The Master Hand awaits anyone who survives the long and difficult road to the Final Destination. This symbolic link between the real world and the imaginary battlefields of Super Smash Bros. Melee is quite a handful in battle, and just because it wears a white glove doesn't mean it fights clean. Get ready to be flicked, swatted, punched, and poked like crazy.''

Brawl
''A being tied to the link between this world, where trophies fight, and the world beyond. The meaning of his existence is unknown, as are his goals, but he seems to have obtained (and kept hidden) a power that borders on absolute. He also seems to feel a certain joy in challenging chosen warriors who've claimed many victories. He waits even now in Final Destination.''

Trivia

 * In Kirby and the Amazing Mirror, Master Hand is a mini-boss throughout the game. Once defeated, Kirby can eat him and become Smash Kirby (He can use all of Kirby's special attacks from Melee. Master Hand also appears later in the game as a Boss along side Crazy Hand.