Aela, the Nightstalker

When this creature transforms into Aela, the
Nightstalker, draw a card, then put a blood
counter on target creature. As long as Aela is
attacking, you may have target creature with a
blood counter block it this turn if able.
Whenever a creature with a blood counter dies,
transform Aela at the beginning of the next
end step.
"You have the blood of the wolf in you."