The Rocket class Heavy guns are slow-shooting guns that have a huge amount of damage. They always decrease the player's speed. In Gun Bros 1, they are mostly the RPB class of weapons. In Gun Bros 2, they diversify.
“The Apocalypse is the gun with the #1 most damage in the game. It is a heavy class gun, but it...The Apocalypse
“The Coronal Ejector is a lethal weapon. Though a slow-shot weapon, this is currently the best...Coronal Ejector