Luminous Broodmoth, Flayer of the Hatebound, and Altar of Dementia

Prerequisites

• Luminous Broodmoth on the battlefield
• Flayer of the Hatebound on the battlefield
• Altar of Dementia on the battlefield

Steps

1. Activate Altar of Dementia by sacrificing Flayer of the Hatebound
2. Flayer of the Hatebound's undying ability and Luminous Broodmoth trigger
3. Resolve the Flayer of the Hatebound trigger, returning it from your graveyard to the battlefield with a +1/+1 counter on it
4. Flayer of the Hatebound enters the battlefield, dealing damage equal to its power to any target
5. The Luminous Broodmoth trigger fails to resolve due to having no legal target
6. Resolve the Altar of Dementia trigger, causing target player to mill cards equal to Flayer of the Hatebound's power
7. Activate Altar of Dementia by sacrificing Flayer of the Hatebound
8. Luminous Broodmoth triggers, returning Flayer of the Hatebound from your graveyard to the battlefield with a flying counter on it
9. Flayer of the Hatebound enters the battlefield, dealing damage equal to its power to any target
10. Resolve the Altar of Dementia trigger, causing target player to mill cards equal to Flayer of the Hatebound's power
11. Activate Altar of Dementia by sacrificing Flayer of the Hatebound
12. Flayer of the Hatebound's undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
13. Flayer of the Hatebound enters the battlefield, dealing damage equal to its power to any target
14. Repeat from step 6

Results

• Infinite damage
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mill
• Infinite sacrifice triggers
• Infinite self-mill