When first introduced, Mimir can be difficult to spot. His naked body is twisted through the trunks of a tall, multi-stemmed tree, looking as though the two have grown together. His head, chest, and one leg are exposed, but his flesh has become bruised, pockmarked, or overrun with green mould.
Thick stems bind his shoulders and elbows, suspending his arms away from his body. His mossy hands are left free, and are the only part of himself that Mimir is capable of moving besides his head.
Mimir is bald, with an overgrown dark grey beard and moustache which are ragged and unkempt. He appears to be in his early seventies, with bushy eyebrows and large bags under his eyes. Mimirâs left eye socket is open and empty, and the iris of his right eye is a brightly glowing circle of gold. Two small, ivory horns protrude from his forehead, and curve back toward the crown of his head before coming to a tapered point. The smoothly rounded surfaces of his horns have been engraved with knotted patterns, and his bare head has rows of faded runes tattooed in greyish blue.