Warren Soultrader + Seedship Broodtender + Reveillark + Boss's Chauffeur + Auriok Champion

Warren Soultrader

Seedship Broodtender

Reveillark

Boss's Chauffeur

Auriok Champion

How it works

1. Activate Warren Soultrader by paying 1 life and sacrificing Reveillark.
2. When Reveillark dies, it triggers, returning Seedship Broodtender and Boss's Chauffeur from your graveyard to the battlefield. Boss's Chauffeur will enter with a +1/+1 counter on it equal to the number of creatures you control.
3. When Seedship Broodtender enters, it, Auriok Champion and Boss's Chauffeur trigger.
4. Resolve the Auriok Champion trigger, causing you to gain 1 life.
5. Resolve the Boss's Chauffeur trigger, putting a +1/+1 counter on Boss's Chauffeur.
6. Resolve the Seedship Broodtender trigger, causing you to mill three cards.
7. Resolve the Warren Soultrader ability, creating a Treasure token.
8. Activate Warren Soultrader by paying 1 life and sacrificing Boss's Chauffeur.
9. When Boss's Chauffeur dies, it triggers, creating a 1/1 Citizen creature token for each +1/+1 counter on it.
10. When the Citizens enter, Auriok Champion triggers that many times, causing you to gain that much life.
11. Resolve the Warren Soultrader ability, creating a Treasure token.
12. Activate Warren Soultrader by paying 1 life and sacrificing a Citizen, creating a Treasure token.
13. Repeat step 12 two additional times.
14. Activate five Treasures by tapping and sacrificing them, adding 3.
15. Activate Seedship Broodtender by paying 3 and sacrificing it, returning Reveillark from your graveyard to the battlefield.
16. When Reveillark enters, Auriok Champion triggers, causing you to gain 1 life.
17. Repeat.

This intricate loop revolves around Warren Soultrader providing the sacrifice outlet and Treasure generation needed to fuel Seedship Broodtender's recursion ability. Reveillark acts as the core engine piece by continuously pulling back Seedship Broodtender and Boss's Chauffeur whenever it leaves the battlefield, while Boss's Chauffeur grows large enough upon re-entry to spawn a swarm of Citizen tokens upon its own eventual death. Finally, Auriok Champion sits quietly on the board to capitalize on the constant creature entries by padding your life total, ensuring you never run out of life to pay into Warren Soultrader's demands.