Idea behind this was to basically piggyback a Lightning Bolt onto an attacking creature. It costs you the creature and here is a 'shields down' risk but the payoff can be huge.

Um; "Target creatures controller sacrifices it" when cast on an opponents creature in their main2...

With that ability, it's possibly too powerful or too cheap. Without it, it's too expensive (two red and sac a creature to deal 3 extra damage? Ouch.)

Oh; hang on - this gained "And is unblockable" while I wasn't looking. Ok; that's now verra nice; assuming "Target creature" should be "Target creature you control" Allowing this to be game-winningly good AND to be perfect removal seems a touch cheap.

May need to add to the CC. Ideally you would use it on your own creature,yes. I was originally going to have this playable only during combat phase and then deal 3 damage to the targeted creature, but this way seemed a bit more elegant as yes, it can be efficient removal at the price of 4 or more damage to the head because, lets face it, you'd only play it on an opponent's creature if you had no oher way of taking it out. But I can see what you mean and will keep an eye on this.

The way it stands right now, Camruth, you can just cast it on your opponent's creature when it has summoning sickness, or after he chose not to attack with it, or after combat when it bounced against your own creature, or during your turn. You almost never take damage. It's about as strong as Diabolic Edict, before using it to boost your own creatures.

I wouldn't try to adjust for that... it seems to defeat the point of the card. It makes more sense if the card just read "you control".

What jm said :) Except it's better than diabolic edict; because you get to choose the creature that is sacrificed.

If you're opposed to "you control" then you could make it "Cast this only before combat" (or only before blockers are chosen?) so that you do at least have to take creature+3 to the bonce to kill an opponents creature with it.

Right now - it's a no risk, , near-perfect (flicker and hexproof can still avoid it; but nothing else, including invulnerable, can) killspell that happens to also be usable as an "Groundstall? Ok, I win." end-game card.

(It's a nice piece of flavour though. "I'm not blocking him! He's on fire! Just leave him alone, he'll stop moving soon enough." Kinda hilarious when used on a Fire Elemental though.)

I was going to say, if you want it to only work during combat, you could say "target attacking creature". (If you keep the sacrifice clause you should probably not let it hit blocking creatures, since then the extra damage doesn't matter and it is just destroy). But even that doesn't worked, because then you could still play it on a blocked creature.

It have the effect intended, I think would have to say "during the declare blockers step", which is also ugly.

I personally don't think letting spells like this hit opposing creatures is a good idea. If a spell has a niche alternative use, I think that's very good, because it lets people discover interesting innovations themselves. But I think this is probably at least as useful as "pay three life, destroy target creature even if it's indestructable or has regenerate" than it as as "deal 3 + N damage to an opponent", so it's unfair that the flavour suggests it only means the second one. It's also true that a card that has two different powerful effects needs to cost more to account for the flexibility.

So I think it needs to go in one of two directions: either embrace the "can eliminate a creature on either side" effect, or take it out and let this just be a normal "get creature through for damage" spell.

Technically, at the moment, in fact it's not usable as removal because you can only sacrifice creatures you control. :P But that makes it unprintably misleading.

I agree: it needs to either embrace the potential for being used on opponents' creatures and say "target attacking creature" and "Cast ~ only before blockers are declared" (and also "its controller sacrifices it"); or prevent it with a simple "target creature you control".

Went with "Target creature you control" to simplify the card.
Kept the cost at for now to make splashing a bit harder, especially for Infect decks where this is especially nasty.