Has anyone ever beaten the Lich?

Every time I run into this guy with a semi-strong build, I think "Oh, maybe THIS time I can take him!" only to be blown the hell out immediately. His regen hits massive numbers, his build constantly freezes you and there's basically no way to punch through his healing or counter his poison early. You're going to bleed out and it's gonna be a painful endeavour.

So has anyone found a way to beat him? Counter him? Find a way AROUND his massive regen to kill him?