Grave-Ridden Vampire

Lifelink
When a creature dies, if this Grave-Ridden
Vampire dealt damage to that creature this turn,
Grave-Ridden Vampire gains indestructible until
your next turn.
Sacrifice a creature: This creature gain power
equal the sacrificed creature's power, and
toughness equal to half of the sacrificed
creature's toughness, rounded down.