And yeah, your point about Graiya sounding god-like is well taken, but to pull out the Hindu religion for a counterpoint, so do most of the Kaurava, who kicked fair amounts of butt against the Pandawa, who were half divine themselves, and were more or less all mortal (if not all entirely human).

Heck, Buddha was mortal and untranscendent for a lot of his early feats – feats that his fellow sages not only could approach, but were considered standard for their calling at the time. I remember a story about one of his early teachers eating only a single grain of rice each day. Yogi were hardcore back then.