Painter's Servant

As Painter's Servant enters, choose a color.
All cards that aren't on the battlefield, spells, and permanents are the chosen color in addition to their other colors.

Teysa, Orzhov Scion

Sacrifice three white creatures: Exile target creature.
Whenever another black creature you control dies, create a 1/1 white Spirit creature token with flying.

Pitiless Plunderer

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")