Campaign Formerly Know as Cousken's
According to the Dwarves, there are three sort of bombs. A B and C. C bombs are the weakest, into this category fall items used as hand granades or small anti creature explosives used in combat. B bombs are mostly used in construction, mining or demolition. These bombs are so high in power a single one is able to collapse a castle, drill out a mountain or create a small lake.
Up until now the A bomb has only existed in theory. The Dwarves of Dun Kraal took great pride in proving the world their mastery over metal, stone and rune in crafting the first one into existence. Ordered by a human lord, the full power of this bomb is highly speculative and has been said only to be usable as political leverage. One would have to be truly mad to release 100 megathaums of magic onto the world.