Mortal wound

[HugPhoenix]

[spoiler='lore']When a monster inflicts 2000 or more battle damage to your life points: Equip that monster with this card. The equipped monster cannot activate its effects, or be tributed or used as any material. It is destroyed during your opponent's next standby phase.[/spoiler]

[Nightmare Stomper]

I like this, but how about a bit more powerful?

 

When a monster your opponent controls inflicts at least 2000 damage to your Life Points: Target that monster, and apply this card's effect. The targeted monster cannot activate its effects, also it cannot be used as a Fusion, Synchro, or Xyz Material for a Summon. While it is face-up on the field, it cannot be Tributed. Banish that monster during your opponent's next Standby Phase, then inflict damage to your opponent equal to the battle damage you took from that monster's ATK.

[magemeek22]

Hmmm...the card has a difficult condition to base activation off of (basically, you'd be in tough times using this card anyways), so I would definitely recommend boosting its power. @Nightmare Stomper's OCG fix seems correct to me, but the additional burn effect is kind of meh (countering fire with fire, essentially).

 

My recommendation: banish the monster. This prevents nasty in-grave effects and is kind of an ultimatum that makes sure the monster is GOING to leave the field without still being useful to the opponent. Also, the fact that this procs during your opponent's next standby phase more than ensures balance, so I wouldn't worry too much about using the banish eff.

[Nightmare Stomper]

You're a genius :P I will incorporate this into my errata.