[Sarinpa1]

It's not impossible to build a tanky enough lich for that to be overwhelming.
I'd much rather see it reduced to -25%/+25%.
Or, something along the route of how some games (namely final fantasy tactics) have undead - they rise after X turns. Way I'd see it ingame, is that upon reaching 0HP, Liches remains would be there, bound to get up in a turn or two, with some % of HP, or something, you having to dish out the damage to fuck the remains up, else they'd rise with full HP.
I know I'm not being very clear and I don't really know how to refine the idea to fit SL, but something along the lines would suit them lore wise and would make them more formiddable, I'd say. Maybe. I don't know.