Endless Waltz

This spell cannot be cast unless you control
a Vampire.
When Endless Waltz enters the battlefield,
choose a Vampire creature you control and a non-Vampire creature target player controls and
tap them. These creatures do not untap as long
as Endless Waltz is on the battlefield. If the
tapped creature target player controls is a
Human, during each upkeep that player loses 3
life and you gain 3 life.