A Final Smash is a Special Attack introduced in Super Smash Bros. Brawl, and it returns in Super Smash Bros. Tourney with a new Special Attack, the Hyper Smash. Final Smashes are incredibly powerful in comparison to most other attacks, generally leaving the user invincible for the move's duration, and, if properly executed, usually have the capacity to KO at least one opponent. Final Smashes performed correctly will give a great advantage, and may help to catch up to others in the game, or vice versa.
To perform a Final Smash, a player must destroy a Gold Smash Ball. Upon the destruction of the Gold Smash Ball, the character will be engulfed in a rainbow-colored aura. If too much damage is taken, the Gold Smash Ball will fly out of the character, giving their opponents another opportunity to gain a Final Smash. To perform a Final Smash, simply press the Special Attack Button. Multiple Gold Smash Balls can't appear in a match at the same time, but another can reappear after the Final Smash is finished; though one Gold Smash Ball and one Silver Smash Ball can appear in a match at the same time. To cancel a Hyper Smash into a Final Smash, the player must press the B button while the Hyper Smash activation sound, which is the same sound that was heard during Street Fighter IV upon the activation of a Super Combo, is playing (it must be playing to cancel a Hyper Smash into a Final Smash, or it won't work).
In Super Smash Bros. Tourney, the sound that will be heard upon the activation of a Final Smash is the sound that was heard during Street Fighter IV upon the activation of an Ultra Combo.