Yahenni, Undying Partisan, and Tromell, Seymour's Butler

Prerequisites

• Yahenni, Undying Partisan on the battlefield
• Tromell, Seymour's Butler on the battlefield

Steps

1. Activate Yahenni by sacrificing the persist creature
2. When the persist creature dies, its persist ability triggers, returning it from your graveyard to the battlefield without a -1/-1 counter on it due to Tromell Resolve the Yahenni ability
3. Repeat

Results

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