Activate Lord of the Forsaken's first ability by paying and sacrificing Oathsworn Vampire.
When Oathsworn Vampire dies, Pitiless Plunderer and Zulaport Cutthroat trigger twice.
Resolve both Pitiless Plunderer triggers, creating two Treasure artifact tokens.
Resolve both Zulaport Cutthroat triggers, causing each opponent to lose 2 life and you to gain 2 life.
Resolve the Lord of the Forsaken ability from step 1, causing target player to mill three cards.
Activate Lord of the Forsaken's second ability by paying 1 life, adding C that can only be spent to cast a spell from your graveyard.
Activate both Treasures by tapping and sacrificing them, adding .
Cast Oathsworn Vampire from your graveyard by paying 1.
Repeat.
This elegant loop transforms a single black mana and a life point into an engine of absolute doom by leaning heavily on overlapping replacement and trigger effects. Drivnod, Carnage Dominus doubles every death trigger that occurs on your board, ensuring that Pitiless Plunderer and Zulaport Cutthroat both trigger twice every time a creature perishes. You feed Oathsworn Vampire directly into Lord of the Forsaken's sacrifice ability to fuel the mill, which conveniently satisfies the vampire's own condition to be cast straight from the graveyard thanks to the life gained from Zulaport Cutthroat. The Treasure tokens generated by Pitiless Plunderer provide the necessary mana to recast the vampire, while Lord of the Forsaken's specialized mana ability bridges any remaining color requirements using paid life, creating an infinite cycle of sacrifice, drains, and recursion.