Ascending the mountain was a little trickier than Arthur had anticipated. He wanted to be civil about his entrance, to at least negotiate Rain's fate. After entering the Uncharted Lands, he became aware of her existence atop the mountain, although his rune did not allow him to communicate with her. The fog had unique qualities of its own, as Arthur could not find the direction to ascend the mountain. However, the fog seemed to disperse once he used his lightning to navigate, albeit in a small radius, but just enough to tell him where to go.
Thus, his journey began toward the mountain top, which took another precious hour, but was necessary to avoid conflict with the clan. Arthur concluded that this place was his hometown, or something of the sort. Even from here, he could feel the wrath condensed atop the black mountain.