Extremis

Enchanted creature gets +1/+1, trample and
"when the enchanted creature is put into the
graveyard, it deals 2 damage to target
attacking creature".
Equip: {0}
"Extremis harnesses our bioelectrical potential. And
it goes... here. This is essentially an empty slot, and
what this tells us is that our mind, our entire DNA in
fact, is destined to be upgraded."
- Aldrich Killian to Pepper Potts