As long as any healing done tot he voodoo doll also ups the opponents hp, then I'm not so bothered by the immolation thing, so that no bonus damage is added. I am curious about if it's a passive ability or not. I'd be disappointed if liquid shadow, a darkness card itself, couldn't deal damage via poisoning a voodoo doll. Also with this concept i hope upgraded voodoo dolls might deal some damage, if just 1.