12.1.8 Any time a creature would block or be blocked by gobbling horror, deal 3 damage to it. Creatures dealt damage this way can’t be regenerated. If gobbling horror would deal damage to a player, prevent it. That player looses 1 life.

art: a serpent monster that looks normal infront of a warrior swinging a sword at it but it slithers around and at its head it is huge from behind.

Original idea was some form of creature that got larger, maybe by creatures dieing or coming into play. Was supposed to work well with the second ability of preventing the damage but not sure if that seems to make any sense. Still working on that.

12.1.9Whenever a creature comes into play under an opponent's control put a +1/+1 counter on Gobbling Horror.

Whenever Gobbling Horror is dealt damage remove all +1/+1 counters from Gobbling Horror. Prevent damage up to how mny counters are removed this way.

If Gobbling Horror would deal damage to a player, prevent it. That player looses 1 life.

Gobbling Horror likes to toy with it's prey.

Also dropped it down to a 1/1. Mana cost should probably be updated but probably still needs alot of tweaking.

The second ability is rather confused. Say this has 4 +1/+1 counters on it and is in combat with a 3/3. What are you expecting to happen?

Wouldn't it remove four counters and prevent up to 4 damage which would mean it would survive as a 1/1?

But what would it do to the 3/3? Deal 5 damage or 1 damage? The wording doesn't actually work either way, because the "Whenever" is trying to prevent the damage after it's already happened, but once I understand what you want I can help you find the wording you want.

I presumed this was supposed to work the same way as the various "If ~ would take damage, instead remove a +1/+1 counter." creatures. But maybe not.

It would still deal 5 damage because once damage and counters are removed / prevented then all damage is already dealt.

looses = loses. I'm sorry about getting uptight about spelling, but that one drives me up a wall.

The problem is, the natural templating for what you've written would have the counters removed at the precise same time that this deals damage. Players would get very confused about whether that means this deals damage equal to its power before or its power after. (By analogy with wither, we can see it would indeed deal the full 5 damage.) It's also rather hard to make the rules remove all the counters whenever any damage would be dealt, while simultaneously starting prevention of up to that many.

(Should the prevention apply just to that moment the damage is dealt, or for the rest of the turn? Say I tap a Prodigal Pyromancer at this when it has 6 counters: all 6 are removed and that damage is prevented. But then if I untap the Pyromancer and shoot at this again, do you want that damage to be prevented too, using up another 1 of the shield? Or should the shield go away after the first damage instance?)

If you want to go with that version, then the templating you want would be something like:

> If damage would be dealt to ~, remove all +1/+1 counters from ~ and prevent up to X of that damage, where X is the number of counters removed this way.

It's pretty unusual and pretty tricky though. It might be simpler to just go with the ability from Protean Hydra:

> If damage would be dealt to ~, prevent that damage and remove that many +1/+1 counters from it.