Hel, the Death-Giver

Return target creature from your graveyard
with converted mana cost X or less to the
battlefield, where X is the amount of life you
gained this turn. That creature is a Zombie in
addition to its other types.
At the beginning of the next turn's upkeep, if
you control another zombie transform Hel, the
Death-Bringer
If Hel, the Death-Bringer dies, exile it instead,
and return it to the battlefield during your next
upkeep.