Nim Deathmantle + Ashnod's Altar + Dryad Arbor + Greensleeves, Maro-Sorcerer

Nim Deathmantle

Ashnod's Altar

Dryad Arbor

Greensleeves, Maro-Sorcerer

How it works

1. Activate Ashnod's Altar by sacrificing Dryad Arbor, adding CC.
2. When Dryad Arbor dies, Nim Deathmantle triggers, causing you to pay 4 to return Dryad Arbor from your graveyard to the battlefield, and attaching Nim Deathmantle to it.
3. When Dryad Arbor enters the battlefield, Greensleeves triggers, creating a 3/3 Badger creature token.
4. Activate Ashnod's Altar by sacrificing the creature token, adding CC.
5. Repeat.

This clever loop turns Ashnod's Altar and Nim Deathmantle into an infinite recycling engine by exploiting the unique nature of Dryad Arbor, which counts as both a land and a creature. When you sacrifice Dryad Arbor to the Altar for mana, Nim Deathmantle steps in to resurrect it straight to the battlefield for a cost of four mana, which is easily paid for using the Altar's sacrifice proceeds and the colorless mana left over. Every time Dryad Arbor returns, Greensleeves, Maro-Sorcerer triggers its landfall ability to produce a 3/3 green Badger creature token. You can then feed this token right back into Ashnod's Altar to sustain the loop indefinitely, generating an unbounded stream of sacrifices, leaves-the-battlefield triggers, and badger tokens.