Athreos, Shroud-Veiled, Resourceful Defense, and Altar of Dementia

Prerequisites

• Athreos, Shroud-Veiled on the battlefield
• Resourceful Defense on the battlefield
• Altar of Dementia on the battlefield
• You control at least two creatures
• At least one creature has coin counter on it

Steps

1. Activate Altar of Dementia by sacrificing a creature with coin counter
2. Athreos and Resourceful Defense triggers
3. Resolve the Athreos trigger, returning that creature to the battlefield
4. Resolve the Resourceful Defense trigger, putting a coin counter on other creature you control
5. Resolve the Altar of Dementia's ability, causing target player to mill equal to sacrificed creature's power
6. Repeat

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mill
• Infinite sacrifice triggers