Athreos, Shroud-Veiled + Blue, Loyal Raptor + Altar of Dementia

Athreos, Shroud-Veiled

Blue, Loyal Raptor

Altar of Dementia

How it works

1. Cast the Dinosaur in your hand by paying its mana cost. It will enter with a coin counter due to Blue.
2. Activate Altar of Dementia by sacrificing the Dinosaur.
3. When the Dinosaur dies, Athreos's second ability triggers, returning the Dinosaur from your graveyard to the battlefield. It will enter with a coin counter due to Blue.
4. Resolve the Altar of Dementia ability.
5. Repeat from step 2.

This clever loop turns Athreos, Shroud-Veiled into an involuntary recycling plant by using its end-step ability to place a coin counter on Blue, Loyal Raptor. Once marked, whenever Blue—or any other Dinosaur entering alongside it—is fed to Altar of Dementia, Athreos immediately intercepts the death trigger to return that creature straight to the battlefield. Because Blue, Loyal Raptor remains on the board with its replacement effect active, every subsequent recursion seamlessly reapplies the coin counter upon re-entry, allowing Altar of Dementia to mill your opponents' entire libraries through an endless cycle of sacrifices.