Activate Warren Soultrader by sacrificing Nether Traitor and paying 1 life.
When Nether Traitor dies, Sek'Kuar triggers, and Luminous Phantom triggers if it is on the battlefield.
Resolve the Luminous Phantom trigger, if applicable, causing you to gain 1 life.
Resolve the Sek'Kuar trigger, creating a 3/1 Graveborn creature token.
When the Graveborn enters the battlefield, Lunarch Veteran triggers if it is on the battlefield, causing you to gain 1 life.
Resolve the Warren Soultrader ability, creating a Treasure token.
Activate the Treasure by tapping and sacrificing it, adding .
Activate Warren Soultrader by paying 1 life and sacrificing the Graveborn.
When the Graveborn dies, Nether Traitor triggers, and Luminous Phantom triggers if it is on the battlefield.
Resolve the Luminous Phantom trigger, if applicable, causing you to gain 1 life.
Resolve the Nether Traitor trigger, causing you to pay to return Nether Traitor from your graveyard to the battlefield.
When Nether Traitor enters the battlefield, Lunarch Veteran triggers if it is on the battlefield, causing you to gain 1 life.
Resolve the Warren Soultrader ability, creating a Treasure token.
Repeat.
This cunning loop hinges on Warren Soultrader as your sacrifice outlet, turning the recurring body of Nether Traitor into a continuous stream of resources while fueling the engine. Whenever Nether Traitor and the Graveborn token generated by Sek'Kuar, Deathkeeper are sacrificed, they trigger Lunarch Veteran // Luminous Phantom—or its front face—to completely offset the life payments with endless lifegain. The Treasure token produced by Warren Soultrader provides the black mana required to trigger Nether Traitor's own resurrection ability from the graveyard, sustaining an infinitely repeating cycle of sacrifices, deaths, and entries.