Felicia, Mayhem Maid

Double-Strike
Retainer- If you control a Vampire Lord, Felicia get's +2/+1 and Lifelink.
{2}{u}: Sacrifice a Artifact: Felicia gains Hexproof and becomes unblockable until end of turn.
{2}{b}: Sacrifice a Artifact: Target Opponent loses life equal to Felicia's power, and you gain that much life.