Pointed Discussion

Nice idea, poor execution. If it only cost R, or gave a starting bonus of +2/+0, or cost R and gave a starting bonus of +2/+0, it might be playable.

Idea - Play red/white and stick this and a pacifism type card on something big your opponent has. Wait 3 turns and... BOOOOM; dead creature and some decent (probably at least 8ish) damage. For max effect use something a-la cage of hands so your pacifism effect can be reused.

I thought it was good until I read "to it's controller". This thing is crap.

This card is: 'Watch your opponent's locked-down creature boil over and explode in his/her face. Laugh.'

It's funny this is rated so low, when Unstable Mutation is rated so high. They're both basically the same thing: Either give one of your creatures a temporary boost (hopefully long enough to kill your opponent), or slowly kill one of your opponent's creatures.

Also note that you only take the damage if the creature dies from overdose of this thing. If the creature dies any other way (say, from combat damage), there's no penalty. That might make this workable in an aggro deck.

@sonorhC: This is totally different from Unstable Mutation.

Unstable Mutation gives +3/+3 immediately and for only , then +2/+2, +1/+1, +0/+0, and then, only then, four whole turns later, starts to kill the creature. This is a total boost of +6/+6, with four attack opportunities. Furthermore, the -1/-1 counters have more interaction effects, usually advantageous (e.g. Heartmender).

Consuming Ferocity only gives +1/+0 immediately for twice the converted mana cost, then +2/+0, and finally +3/+0: it never gives it a bigger bonus because the third counter instantly kills it. Even if it makes it to this point, it will hit its controller (likely you) for 4+ damage. This is a total of +6/+0, with three attack opportunities.

Used to boost your own creatures, it provides half the effect at twice the cost, is far less aggressively paced, and is almost certain to kill your creature and deal large damage to you before it can attack a fourth time. As removal, it's also terrible, as the target will live for three more attack phases, beating you for an extra 6 damage too!

There are only a couple instances where Consuming Ferocity would be preferable over Unstable Mutation, and only two good ones.
The first is Spirit Link. Are you going to attack me? I'll just gain it back. Are you going to block me? I'll gain some life off of that, thank you very much. Are you going to kill your own creature? Great; less removal for me to deal with. Are you going to sit back and let it die? It's the creature that deals the damage, so I think I'll gain an equal amount of life, if you don't mind. It's by no means a flawless strategy, but a funny one.
The second is Indestructibility (and preferably something like Pacifism or, even more amusingly, Spirit Link). Enjoy the increasing damage!

The other instances are in mono- decks (which can't play Unstable Mutation), or for the purpose of directly destroying enemy creatures without specifically investing for Fissure or Cinder Cloud, speeding things up by means of something like Doubling Season or Paradox Haze. It's a shame the Oracle wording made is so that Doubling Season won't save the creature, since the original wording makes it lethal only at exactly three counters.

This isn't a good card, of course, but I don't think it deserves such an awful rating. Note that this only says "non-wall". This means that you can play it on creatures with defender that don't have the wall subtype. In that case, it's simply three damage to your opponent after three turns. Maybe more.

If they control a creature with defender to begin with. That's also not a wall.

Okay, maybe it is really terrible.

Ordeal of self-destruction?

I might be reading this wrong, but it says the creature deals an amount of damage equal to its power, and not just the +1x3 that this card gave it. It's situational, but this card could win you the game if you have an opponent with a hugely powerful creature that you're just throwing 1/1s or some such at every turn to stop from damaging you.... you might even buff that enemy creature the turn before it gets buried if you can deal with the damage.

Idea: Use this alongside Maze of Ith to make a creature ragequit the maze.

...Yeah, okay, it's a bad card. But it's an interesting bad card, and that just means there's lots of room for improvement:

"I've been remaking (and improving upon) Consuming Ferocity for years."
--Mark Rosewater, markrosewater.tumblr.com/post/73003104513/

This reappeared most recently in the really cool Ordeal cycle in Theros. Hey, sometimes bad cards open doors and let good ideas slip through.