15 Jun 2010
The destroyed creature's last existence on the battlefield is checked to determine its toughness.
15 Jun 2010
If the targeted creature is an illegal target by the time Vendetta resolves, the spell doesn't resolve. You won't lose life.
15 Jun 2010
If the targeted creature isn't destroyed due to umbra armor's effect, Vendetta continues to resolve. You lose life equal to the creature's current toughness (after the Aura with umbra armor has been destroyed).