Ōshū has many legends revolving around the Extremis trio of Pokémon, but the one that most often appears is the landbound moving mountain, Frimastodon. The towering beast spends most of its time slumbering, half-buried in the soil of the wilderness, overgrown with plants in such a fashion as to be indistinguishable from the hills and peaks around it.

Firmastodon is said to be peaceful to a point, but will not tolerate harm to the wilds around it, or the capture of the Pokémon that call its craggy, earthen back home. Of the Extremis, Firmastodon is the most recently and regularly active, having attacked logging companies in southern Opoc, and mining crews in the mountains bordering Collines Verdes. Any effort to follow it and discover its resting place is usually shrouded in an obscuring fog, and it always seems to have a habit of finding isolated, seldom-intruded upon territory to rest within.

To see the mighty beast truly at full power, though, one need only look back upon the damage it has dealt, and halted, as the pivot point for the massive confrontations between Abyddon and Whelkin, the other Extremis beasts. As the only force known that can repel, interrupt or control the other behemoths, Firmastodon is easily one of the great powerhouses of the Pokémon world.

Despite this, it rarely shows great aggression toward humans who leave things well enough alone, and only attacks Pokemon that dare to attack it first. It tends to make quick work of most opposition with its six powerful, trampling legs, strong tusks, grasping trunk and boulder-heaving habits. Needless to say, Firmastodon is the immovable object to the unstoppable force of its "kin" in the Extremis trio.

Firmastodon, the Slumbering Mountain Pokémon, No. 03 in the Ōshū Legendarium.

Art by  Goatmystic, who did an amazing job. Any questions, feel free to ask below.