Activate Warren Soultrader by paying 1 life and sacrificing the persist creature.
When the persist creature dies, its persist ability triggers, returning the persist creature from your graveyard to the battlefield with a -1/-1 counter on it.
When the persist creature enters, Guide of Souls triggers, causing you to gain 1 life and get E.
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 brilliant loop transforms your graveyard into an endless engine of wealth and growth, fueled by the recursive nature of a persist creature. By feeding that creature to Warren Soultrader, you immediately generate a Treasure token while triggering the creature's return to the battlefield with a -1/-1 counter. That entering Treasure is the vital spark that prompts Mm'menon, Uthros Exile to place a +1/+1 counter on the returning creature—which conveniently neutralizes the -1/+1 counter and resets the persist loop entirely. Meanwhile, Guide of Souls watches the creature reenter the battlefield to pad your life total and fill your reserves with energy counters, ensuring you gain boundless resources from a single sacrificed soul.