Beifong's Bounty Hunters + Spawning Pit + Down in the Valley

Beifong's Bounty Hunters

Spawning Pit

Down in the Valley

How it works

1. Activate Spawning Pit by sacrificing another nonland creature you control.
2. When the creature dies, Beifong's Bounty Hunters triggers, earthbending a land.
3. Resolve the Spawning Pit ability.
4. Activate Spawning Pit 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 Spawning Pit ability.
8. Repeat.