The Eye Biting Man is a serial killer (?) operating out of North Dakota/Montana. He apparently helped Tucker with a little trepanning.

Google only gives 2 hits. This from Greg Stolze: "The Eye Biting Man is entioned in passing in Lawyers, Guns and Money (one of the psychologists ran into two widely separated kids who'd run afoul of it), I THINK there might be a mention in Hush Hush, and it gets referred to again in the upcoming adventure anthology. It's just something I thought up which I hope never gets explained, ever."

And this from Rob's UA Rough Guide: "The Eye-Biting Man murders unchecked throughout the northern U.S. and southern Canada, if he’s not just an urban legend."

[Jere:] I always thought this was a homage of Rob's towards the Sandman character the Corinthian.

[Rob:] The sentence from the Rough Guide appears in the UA rulebook, so if anyone is referencing Sandman, it's Tynes and Stolze, not me. That said, the evocative name certainly makes me think of the Corinthian, and of various messy things one could do with eyeballs and teeth, and also, indirectly, of trepanation. But the somewhat blander origin of the name is probably that "eye-biting" is a term for either giving or warding off the evil eye. The evil eye is traditionally witch woman's magic, so an eye-biting man is an unusual and dangerous character, but he doesn't necessarily have teeth for eyes or eat other people's eyes out of their heads.