Kaya the Inexorable + Wormfang Manta + Hushwing Gryff + Altar of Dementia

Kaya the Inexorable

Wormfang Manta

Hushwing Gryff

Altar of Dementia

How it works

1. Activate Kaya the Inexorable's first ability by putting a loyalty counter on it, putting a ghostform counter on Wormfang Manta.
2. Activate Altar of Dementia by sacrificing Wormfang Manta.
3. When Wormfang Manta dies, its second ability and its ghostform ability trigger.
4. Resolve the ghostform trigger, returning Wormfang Manta from your graveyard to your hand and creating a 1/1 Spirit creature token.
5. Resolve the second trigger, causing you to take an extra turn after this one.
6. Resolve the Altar of Dementia ability, causing target player to mill cards equal to Wormfang Manta's power.
7. Cast Wormfang Manta by paying 5.
8. Wormfang Manta's first ability does not trigger due to Hushwing Gryff.
9. Repeat each turn.

This elegant loop turns Wormfang Manta's severe drawback into a continuous engine for infinite turns. By using Kaya the Inexorable's ghostform counter to repeatedly return the Manta to your hand when sacrificed to Altar of Dementia, you trigger the Manta's departure clause to bank extra turns. The brilliant linchpin of the strategy is Hushwing Gryff, whose static ability suppresses the Manta's enters-the-battlefield trigger so you never skip your own turns while locking the opponent out of the game entirely.