I can understand the logic for it not triggering if the creature dies. The thing is I'm afraid its uses would be even more limited if smaller creatures don't have a chance to use it. It would give the opponent another reason not to bolt that Giant Frog or Vampire or whatever.
I think that not triggering death effects makes more sense (and is how Voodoo Doll currently works), and you should always go with what makes sense, rather than going with what doesn't really make sense just because of some gameplay detail. After all, there are many ways to buff a card.
You mentioned its rather situationally UP. Would a cost reduction be enough to fix that problem?
Well, it doesn't really fix the problem because all it does is makes the card cheaper. And if you have a dead card in your hand, it doesn't even matter what it costs because you won't play it. I think this card has a fundamental problem of needing a creature before it does anything, and even after that, it might not do anything.
I'm honestly afraid making it a creature would make it even more situational.
I disagree. Good thing about creatures is that they are never 100% situational because even though their abilities might be useless, they still attack and do damage each round. You can also use creatures for other things like sacrificing and triggering death effects. With spells it's usually different because if the spell doesn't benefit you, it's pretty much 100% useless.
The way the card looks now, I don't know how it could be effectively used in a deck. If you must make it a spell, you should look into making the card effect ALL your creatures, not just one. This way it could actually be useful. This would of course mean some other tweaking like changing the cost etc.
