In the video games, the Bombs, as their name implies, will oftentimes explode, delivering a heavy amount of damage to the opposition. This move is very common in their enemy counterparts as well.
In their debuting appearance, Rydia could learn this summon if a Bomb enemy dropped a specific type of item that taught her this. Summoning one will cost a measly 10 MP. The damage it delivers will be the same amount of health that Rydia has, meaning the healthier you are, the more potent this attack will become. In Revenant Wings, its standard attack is nowhere near as powerful as the one that causes it to self-destruct.