Beifong's Bounty Hunters + Ashnod's Altar + Down in the Valley

Beifong's Bounty Hunters

Ashnod's Altar

Down in the Valley

How it works

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