Bob-ombs can be picked up by any player and subsequently thrown at opponents. Being an explosive, the item can easily inflict large damage and knockback to other players, but it can also potentially harm the attacker. Bob-ombs also explode if they are simply hit by an attack.
When a Bob-omb is held by a player for a while, it will begin flashing red, and shortly after will automatically explode in the holder's hands. While it is flashing red to signify its imminent detonation, it will be more powerful than usual, but it is also close to exploding, making for a risk-reward scenario. A held Bob-omb can also be detonated in the holder's hands if they are attacked and the attack hits the Bob-omb.
If a Bob-omb is not picked up, after a while, it will stand up and begin to walk back and forth on the platform it spawned on, turning around at edges. In this state, it will explode if it walks into a player. In Super Smash Bros. 4, it is possible to pick up the item after it starts walking. If it has not exploded after a brief period of walking, it will stand still while flashing red, and then explode, causing damage and knockback to anyone nearby. In SSB4, if a Bob-omb is close to any fighters, it will walk towards them when it starts moving, making it more dangerous than in previous games.
In Super Smash Bros. Ultimate, Bob-ombs will meteor smash opponents when thrown downward. Otherwise, the knockback is diagonally upward as with previous installments. In addition, Bob-omb explosions will no longer harm the user. Much like Gooey Bomb before it explodes, characters will have a surprised look if Bob-omb is about to explode near them.
The Bob-omb is also one of the various unusual items Peach can pluck via her Vegetable special move. The chance of her plucking a Bob-omb is approximately 1/232, but in all games she has appeared in, it can potentially act as her most powerful attack.
In Sudden DeathEdit
From Melee to Smash 4, if a Sudden Death match lasts for too long and a winner hasn't been announced, Bob-ombs will begin to fall from above the stage, instantly exploding upon striking players or the stage. They are intended to end a match more quickly, but can still be grabbed in midair. These Bob-ombs can be avoided by camping in certain places on some stages, but on most stages there is no completely safe position that can be occupied indefinitely. They can also be avoided by stalling on edges, but this also cannot be done indefinitely except through planking. They can not be absorbed or reflected.
The falling Bob-ombs do not appear in Super Sudden Death.