Gehrman, the first hunter

Haste, Vigilance

When Gehrman enters the battlefield or attacks,
create blood tokens equal to the amount of life target opponent has lost this turn.
If a creature you control would be destroyed, you
may sacrifice blood tokens equal to its Mana value,
then exile that creature and return it to the battlefield.
Blood tokens you control gain, "creatures you
control gain +1/+0".