Warren Soultrader + Seedship Broodtender + Reveillark + Boss's Chauffeur + Thunder of Unity

Warren Soultrader

Seedship Broodtender

Reveillark

Boss's Chauffeur

Thunder of Unity

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, Thunder of Unity and Boss's Chauffeur trigger.
4. Resolve the Thunder of Unity trigger, causing you to gain 1 life and each opponent to lose 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, Thunder of Unity triggers that many times, causing you to gain that much life and each opponent to lose 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, Thunder of Unity triggers, causing you to gain 1 life and each opponent to lose 1 life.
17. Repeat.

This intricate loop turns the sacrifice engine of Warren Soultrader into a lethal drain and token-generating machine by repeatedly cycling Reveillark. When Reveillark hits the graveyard, its leaves-the-battlefield trigger pulls back both Seedship Broodtender and Boss's Chauffeur, seeding the board with ETB triggers. Meanwhile, Thunder of Unity quietly amplifies every single creature entry into a life swing, turning the resulting swarm of Citizen tokens from Boss's Chauffeur into an overwhelming drain for your opponents. Seedship Broodtender does double duty here, not only milling your deck to set up the graveyard but also providing the crucial recursion mana to bring Reveillark right back home.