One of the primal dragons, magma dragons dwell on the Plane of Fire, border regions of the Plane of Earth, in remote volcanic lairs or deep underground. Unlike most dragons that dwell in such locations (especially the fiery reds), magma dragons are not evil. But they are as tempestuous as the volcanoes they resemble, so when they do eventually (and inevitably) explode into anger, the results are similarly catastrophic.
Small for his age, the magma dragon Clasm has left his home plane for the Plane of Earth. The cold makes him sluggish and irritable, but the shaitans give him so many fascinating things to smelt and so many alien creatures to burn and devour. The runt plans to return home triumphant with geodes packed with bushels of gems and a hide hardened from consuming so many denizens of Earth.
Magma dragons regard the creation of firearms with fascination. Tyrakolyx thinks it is an abomination, and uses his skills to swim through magma flows and lava tubes to destroy the gunworks of the dwarves. Pyre of Might sees firearms as a glorification of his element. He has commanded his army of duergar and azer slaves to come up with a bombard big enough for a dragon to wield, but his violent rages at every setback continue to delay the project.
Once a great fiery terror, the great wyrm Allikaliki’i is content now to slumber and practice various stratagems on his giant obsidian game boards. (The playing pieces are old foes he entombed in lava.) Two new developments have roused him from his retirement: the revelation that a pair of underworld dragon twins have been tunneling throughout his territory for months without him noticing, and what they found there—an ark containing four slumbering tzitzimitls. But since most other dragons only know him as Mad Tephra, Doom of the Western Isles, he doesn’t know how to go about asking for advice or aid in a fashion that doesn’t involve threats, magma breath, and walls of fire.
—Pathfinder Bestiary 2 100–101