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The energy bazooka is a large-scale artillery weapon capable of being handled by a single individual.
Stadra Ah Mun makes use of this bazooka to clear out a swath of Centurions invading the Maytorian resistance's hideout in a bombed-out trade center, thus preventing Boomer and Starbuck's position from being overrun.
Boomer notes that he's seen nothing like it on Galactica (Classic Battlestar Galactica Vol. 1 #2).