Activate Warren Soultrader by paying 1 life and sacrificing the persist creature.
When the persist creature dies, its persist ability and Elas il-Kor's second ability trigger.
Resolve the Elas il-Kor trigger, causing each opponent to lose 1 life.
Resolve the persist trigger, returning the persist creature from your graveyard to the battlefield with a -1/-1 counter on it.
When the persist creature enters, Elas il-Kor's first ability triggers, causing you to gain 1 life.
Resolve the Warren Soultrader ability, creating a Treasure token.
When the Treasure enters, Mm'menon triggers, putting a +1/+1 counter on the persist creature.
Repeat.
This clever loop turns the cycle of life and death into an endless engine of profit, fueled entirely by a creature returning from the graveyard via persist. By sacrificing that creature to Warren Soultrader, you immediately trigger Elas il-Kor, Sadistic Pilgrim to drain your opponents of their life. As the creature returns, Elas il-Kor gains you a life back while Mm'menon, Uthros Exile places a +1/+1 counter on it to immediately neutralize its -1/+1 counter drawback. Meanwhile, Warren Soultrader's sacrificed offering creates a Treasure token, whose own entry triggers Mm'menon, Uthros Exile yet again to keep your board growing stronger.