Surrak and Goreclaw, and Yahenni, Undying Partisan

Prerequisites

• Surrak and Goreclaw on the battlefield
• Yahenni, Undying Partisan 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 with a -1/-1 counter on it
3. When the persist creature enters, Surrak and Goreclaw triggers, putting a +1/+1 counter on the persist creature
4. Resolve the Yahenni ability
5. Repeat

Results

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