Beifong's Bounty Hunters + Yahenni, Undying Partisan + Down in the Valley

Beifong's Bounty Hunters

Yahenni, Undying Partisan

Down in the Valley

How it works

1. Activate Yahenni by sacrificing another nonland creature you control.
2. When the creature dies, Beifong's Bounty Hunters triggers, earthbending a land.
3. Resolve the Yahenni ability.
4. Activate Yahenni by sacrificing the land.
5. When the land dies, Beifong's Bounty Hunters triggers, returning the land from your graveyard to the battlefield tapped.
6. When the land enters, Down in the Valley triggers, creating a creature token.
7. Resolve the Yahenni ability.
8. Repeat.