G&W moves around the stage, body does damage, extending tentacles do damage
Mr. Game & Watch's Final Smash is based off of the Game & Watch game Octopus. Simply put, Mr. G&W transforms into a large octopus that float-crawls freely (quite slowly) through the stage. Even though the Octopus looks like it's flying, it still requires terrain in order to move, which results in a self-destruct if it falls off the stage, although it can jump and double-jump a small bit. Out of its eight legs (1 of which can't be seen), four of them can extend to about 7 times their length. Normally, only the body will damage the opponents, but if the tentacles are extended, only the tips of the tentacles will damage opponents until they withdraw. The tentacles in the back deal less damage than the ones in the front, which can be a problem since the Octopus can't turn around. Touching the G&W Octopus causes 16% of damage. The Final Smash lasts about 17 seconds. Whilst activated, most of the screen turns slightly white, (causing the screen to somewhat resemble a Game & Watch's white background) and a strange noise is heard.
Octopus was a Game & Watch game where three treasure hunting divers avoided a giant octopus guarding a sunken pirate ship and collected its sunken treasure. If one of the divers got caught by the octopus, the next diver would come down and substitute. The octopus would keep watch over the ship until all of the divers were caught. Mr. Game & Watch's Up-Smash attack also originates from Octopus, where he uses his diver's helmet to headbutt his opponents.
Mr. Game & Watch's Final Smash. He turns into the huge cephalopod that made its debut in the Game & Watch game Octopus. Of course, you can damage enemies by running into them, but you can do more damage by pressing the attack button to extend four arms and launch foes. In the original Octopus game, you had to avoid the octopus while salvaging treasure from the sea.