What is a smash?

Answer 1

A Final Smash is an attack that each character in the game Super Smash Bros. Brawl possesses. The Final Smash is the most devastating attack a character can use.

A Final Smash can only be used after obtaining an item called a Smash Ball. Players attack the Smash Ball until it breaks. It they break it, the next attack they use will be their Final Smash; the Smash varies from character to character.

Quote from Masahiro Sakurai:

The Final Smash is a secret skill that can be performed but once…and only after obtaining an item called the Smash Ball, which is a precious item, indeed. The basic gist of it? I suppose you could say it's kind of like a powerful and personalized hammer. (Or maybe not…)

If you have high damage, and you are attacked by a powerful hit, you may lose the smash ball, allowing other players to get it while you flinch. If you keep dying, sometimes you get something called a pity final smash. The pity final smash makes you look like you just got a smash ball when you come back in, allowing you to use your final smash that one time.