Devita, The Black Queen

Partner with Taven, Blood Sworn(When this
creature enters the battlefield, target player may put
Taven into their hand from their library, then shuffle.)
Humans your team controls have "Sacrifice this creature, Regenerate target vampire."
Whenever a creature dies, if it's a human put
a +1/+1 counter on Devita. If it's non-human you
may pay 2 life: Return target human your
graveyard to your hand.