Actaeon

this is when Actaeon is turning into a red deer. the final step has to be drawn still...
for the ones who don't know the myth:

During a hunt, he left the party and wandered alone through the forest when he suddenly came upon a clearing. There he saw the goddess Artemis bathing in a large pool, surrounded by her nymphs. When they noticed the hunter they flew themselves before the goddess, but he had already seen her splendid nakedness. Angered, she turned him into a stag for she refused to let any mortal say that he had seen Artemis naked.

Actaeon moved away from the clearing feeling different and confused, not yet realizing what had happened to him. The truth hit him when he saw his own reflection in a river and he knew he was no longer human. In the distance he heard the sound of his own hounds. A brief moment of joy quickly turned into fear when he realized they were hunting him now, not recognizing their former master. He fled but was eventually overrun and torn to pieces.