Announced at E3 2006, The Smash Ball (formerly called a Smash Emblem or Smash Orb by fans) is an item shown to debut in SSBB. It appears to allow the user to activate an especially powerful Final Smash attack.
To use the Smash Ball, the characters must attack the Smash Ball until the screen darkens and he/she/it begins to glow. The attack can be unleashed at any time, and can only be used once, after you get the Smash Ball by pressing the Special Move button. However, the Smash Ball can be knocked out if the character with the item is damaged enough.
The Smash Ball can move around on its own, making it harder for players to use; it must be attacked by the players until it breaks, and whoever breaks it will be able to use their Final Smash. This should not be confused with a normal item as it grants the user a special attack; nevertheless, it can be turned off in the Item Switch option for those who wish to battle without absurdly powerful attacks, or even any items at all.
If no one breaks the Smash Ball after a long enough period of time, it flies away. It can also be destroyed by the stage (ex: Norfair's lava).
Originally, it was thought that the Smash Ball could only be used by a character once per battle, due to the way that the DOJO!! worded it. As it turns out, it simply meant that a character could only use a Final Smash once per Smash Ball.