Kodama of the East Tree + Petrified Field + Echoing Deeps + Rampaging Baloths + Horizon Explorer

Kodama of the East Tree

Petrified Field

Echoing Deeps

Rampaging Baloths

Horizon Explorer

How it works

1. Play Petrified Field.
2. When Petrified Field enters the battlefield, Kodama of the East Tree and Rampaging Baloths trigger.
3. Resolve the Kodama of the East Tree trigger, putting nothing onto the battlefield.
4. Holding priority, activate Petrified Field's second ability by tapping and sacrificing it, returning Echoing Deeps from your graveyard to your hand.
5. Resolve the Rampaging Baloths trigger, creating a token.
6. When the token enters the battlefield, Kodama of the East Tree triggers, putting Echoing Deeps from your hand onto the battlefield untapped as a copy of Petrified Field.
7. When Echoing Deeps enters the battlefield, Rampaging Baloths triggers.
8. Holding priority, activate Echoing Deeps using Petrified Field's second ability by tapping and sacrificing it, returning Petrified Field from your graveyard to your hand.
9. Resolve the Rampaging Baloths trigger, creating a token.
10. When the token enters the battlefield, Kodama of the East Tree triggers, putting Petrified Field from your hand onto the battlefield.
11. When Petrified Field enters the battlefield, Rampaging Baloths triggers.
12. Repeat from step 4.

This loop turns a simple land drop into an endless cycle of creation, fueled by the recursive land-swapping power of Petrified Field and Echoing Deeps. With Kodama of the East Tree and Horizon Explorer keeping the lands entering smoothly and untapped, every time a land hits the battlefield, Rampaging Baloths triggers to spawn a Beast token. That token's entry triggers Kodama of the East Tree to instantly drop the other land from your hand, which you can immediately sacrifice to retrieve the first one from your graveyard and keep the engine churning forever.