Yenna, Redtooth Regent + Agatha's Soul Cauldron + Ashnod's Altar + Sparring Mummy

Yenna, Redtooth Regent

Agatha's Soul Cauldron

Ashnod's Altar

Sparring Mummy

How it works

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

This fascinating loop turns Yenna, Redtooth Regent into an enchantment-copying engine by treating Sparring Mummy as an Aura, cleverly utilizing its creature type while it's temporarily attached. To fuel this recursion, Agatha's Soul Cauldron holds the key by granting Yenna the ability to exile cards and place +1/+1 counters, though in this case its mana-fixing and counter-granting presence sets the stage. As the cloned Mummy repeatedly enters the battlefield, its triggered ability untaps Yenna, while Ashnod's Altar promptly sacrifices the token to generate the necessary colorless mana to keep the process going.