Ashnod the Uncaring + Akul the Unrepentant + Cloudstone Curio + Underworld Hermit

Ashnod the Uncaring

Akul the Unrepentant

Cloudstone Curio

Underworld Hermit

How it works

1. Activate Akul the Unrepentant by sacrificing three creatures.
2. Ashnod the Uncaring triggers, copying Akul the Unrepentant's ability.
3. Resolve the copy of Akul the Unrepentant's ability, putting Underworld Hermit from your hand onto the battlefield.
4. When Underworld Hermit enters the battlefield, it and Cloudstone Curio trigger.
5. Resolve the Underworld Hermit trigger, creating a number of 1/1 Squirrel creature tokens equal to your devotion to black.
6. When the Squirrels enter the battlefield, Cloudstone Curio triggers that many times, returning nothing to your hand from the battlefield.
7. Resolve the Cloudstone Curio trigger from step 4, returning Akul the Unrepentant from the battlefield to your hand.
8. Resolve Akul the Unrepentant's ability from step 1, putting it onto the battlefield from your hand.
9. When Akul the Unrepentant enters the battlefield, Cloudstone Curio triggers, returning Underworld Hermit from the battlefield to your hand.
10. Repeat.

This fascinating loop relies on Akul the Unrepentant to cheat big creatures into play by sacrificing three creatures, which immediately prompts Ashnod the Uncaring to double the trouble by copying that activation. When Underworld Hermit hits the board as a result, its entry generates a swarm of Squirrel tokens that fuels your devotion while setting up Cloudstone Curio's bounce triggers. Cloudstone Curio carefully orchestrates the dance by returning Akul to your hand so it can be replayed, which in turn triggers the Curio to bounce the Hermit right back to your hand to start the whole cycle anew.