Fire Bomb, Cluster Bomb, and Carpet Bomb are a series of Mars attack Psynergies featured in both Golden Sun games. It is available exclusively to the Ninja class series. Hence, all of the Adepts in your party, except for Mia and Piers, can use this series of Psynergy.
Fire Bomb: "Attack with a bomb blast.": This costs 5 Psynergy Points, has a base power of 35, and has a range of three targets. There is a small explosion at the base of the enemies. It is available at level 6.
Cluster Bomb: "Attack with a bomb blast.": This costs 11 Psynergy Points, has a base power of 65, and has a range of five targets. There is a larger explosion at the bast of the enemies and it is available at level 16.
Like Gale, the Fire Bomb series is weaker than its counterpart, the Blast series. This does give it a slight advantage over Blast, however, as it costs less PP to cast. Despite all this, the Fire Bomb Psynergies are the only Mars Psynergies available to the Ninja classes, making them valuable to any Adept using those classes.