Nim Deathmantle + Ashnod's Altar + Requiem Angel

Nim Deathmantle

Ashnod's Altar

Requiem Angel

How it works

1. Activate Ashnod's Altar by sacrificing a nontoken non-Spirit creature, adding CC.
2. When the creature dies, Requiem Angel and Nim Deathmantle triggers.
3. Resolve the Requiem Angel trigger, creating a 1/1 Spirit creature token.
4. Activate Ashnod's Altar by sacrificing the Spirit, adding CC.
5. Resolve the Nim Deathmantle trigger from step 2, causing you to pay 4 to return the non-Spirit creature from your graveyard to the battlefield, and attach Nim Deathmantle to it.
6. Repeat.