I dont believe it will be a used card. If healing it / increasing its life (like using Basilisk) have the same effect to the opponent health, looks like its completely useless. I also dont know why you all are discussing this + cremation. This card say "damage inflicted to this creature", and cremation does NOT inflict any damage. Im not even sure if Rage Potion inflict damage, too. Even if it does, using more than once will make the doll very vulnerable. It will be easy to kill, and of course people and even AI (usually) will prefer get 3 damage than let the opponent have a 12/3 creature. If the damage can be reflected, useless is the word.
The single use to me seems to be with gravity pull, and it seems not strong for a 2 card from different elements combo. IF the opponent dont get any heal or health improvments, it could be used with Earth Nymph, or Angels, but cant see other uses.
I would suggest it getting a boost when destroyed, like "deals X damage when destroyed". Even in this case, dunno if it will be played.
Also, I agree that it has nothing to do with the assassin card idea, and I think the picture is terrible. Looks like the doll is smiling, lol.