Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight, Flayer of the Hatebound, and Yahenni, Undying Partisan

Prerequisites

• Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight on the battlefield
• Flayer of the Hatebound on the battlefield
• Yahenni, Undying Partisan on the battlefield

Steps

1. Activate Yahenni by sacrificing Flayer of the Hatebound When Flayer of the Hatebound dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
2. When Flayer of the Hatebound enters, it triggers, dealing damage equal to its power to any target
3. Activate Yahenni by sacrificing Flayer of the Hatebound When Flayer of the Hatebound dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
4. When Flayer of the Hatebound enters, it triggers, dealing damage equal to its power to any target
5. Resolve both Yahenni abilities from step 1 and 4
6. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite damage
• Infinite death triggers
• Infinite sacrifice triggers