Smash Ball (スマッシュボール) is an item first introduced in Super Smash Bros. Brawl, that also appears in Super Smash Flash 2. This item floats all over the stage for a certain time unless it floats away or a character breaks it by pummeling it at a certain damage. When broken, a colorful flame starts burning on the character. Then it allows the character who broke it to perform their Final Smash by performing a standard special move.
To use the Smash Ball, the characters must attack the Smash Ball until it breaks. Once it is destroyed, the player whose attack broke the Smash Ball goes into "standby mode," in which the character is surrounded by a rainbow-colored flame. The Final Smash can then be unleashed at any time by pressing the standard special move button. After using a Final Smash, the character is no longer in standby mode and must break another Smash Ball before using it again.
If a character takes enough damage or is hit by a strong attack while in standby mode, there is a chance that they may lose the Smash Ball, which then begins to move about the screen again. Any projectile can aid in collecting it. The Smash Ball moves around on its own, making it harder for players to use; but most of the time it remains static so players can attack it.
The camera treats Smash Balls the same way that it treats characters. Smash Balls do not vanish by being forced off the stage like other items, so a Smash Ball sent off the screen can pull the camera away from the characters. If no one breaks the Smash Ball after a long enough period of time, it flies away and/or disappears.
In early demos of Super Smash Flash 2, before Brawl was released, the player originally had to grab a Smash Ball from the ground like a regular an item and activate it not only by using the standard special move button, but also by obligately pressing the shield button alongside the aforementioned standard special move button. This has been removed in later demos.
In patches of demo v0.9a before v0.9.0.1956, as well as in early patches of demo v0.9b, the Smash Ball was unavailable due to unfinished Final Smashes.
This happened again in the Beta version, presumably for the same reason.