Yenna, Redtooth Regent + Agatha's Soul Cauldron + Ashnod's Altar + Coercive Recruiter

Yenna, Redtooth Regent

Agatha's Soul Cauldron

Ashnod's Altar

Coercive Recruiter

How it works

1. Activate Coercive Recruiter using the Licid's ability by paying its activation cost, attaching Coercive Recruiter to Yenna and causing Coercive Recruiter to become an Aura.
2. Activate Yenna by paying 2 and tapping it, creating a token copy of Coercive Recruiter.
3. When the Coercive Recruiter token enters, it triggers, untapping Yenna.
4. Activate Ashnod's Altar by sacrificing the Coercive Recruiter token, adding CC.
5. Repeat from step 2.

This fascinating loop turns an unusual rules interaction into an engine of endless sacrifices. With Agatha's Soul Cauldron granting activated abilities from the graveyard, Coercive Recruiter's ability is bestowed onto Yenna, Redtooth Regent (presumably via a Licid card in the graveyard, allowing it to become an Aura). Yenna can then tap to create a token copy of Coercive Recruiter; because that token enters as an Aura, it untaps Yenna to keep the chain going. Finally, Ashnod's Altar converts the freshly minted token into a steady stream of colorless mana, fueling Yenna's copying cost indefinitely and churning out infinite enters-the-battlefield, leaves-the-battlefield, and death triggers.