Big Black Mountain is dark and deep, its boundaries unknown.
The older generation of Monster Hunters from Tongxian City usually divide Big Black Mountain into three sections: the Outer Mountain, the Inner Mountain, and the Deep Mountain.
The Outer Mountain of Big Black Mountain is where most Monster Hunters hunt Monster Beasts; the area has few poisons, lighter miasma, and although the terrain is treacherous, it's not exceedingly dangerous.
The Monster Beasts in the Outer Mountain are mostly at the middle phase of the first grade, with the occasional late phase first grade Monster Beast appearing, but not often.
The Inner Mountain of Big Black Mountain, on the other hand, is extraordinarily perilous, riddled with poisonous creatures, thick miasma, and fog that confounds the mind.
The Monster Beasts in the Inner Mountain are mainly at the late phase of the first grade, and occasionally there might even be a second grade Monster Beast.
