The Sisters Three

Whenever an aura curse enter the battlefield, put
a +1/+1 counter on each other warlock, shaman,
or cleric creature you control.
{b/r}{t}, Sacrifice a creature: create black aura curse enchantment token attached to target player with "deals 1 damage to
that player or a planeswalker that player controls".
{b/g}{t}, create a 1/1 black Rat creature token.
{2}{u}{t},scry 3, draw a card.