Dominion Saboteur, and Aerie Ouphes

Prerequisites

• Dominion Saboteur on the battlefield
• Aerie Ouphes on the battlefield

Steps

1. Activate Dominion Saboteur by sacrificing it
2. When Dominion Saboteur dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
3. As it enters, choose to have it copy Aerie Ouphes, and then also enter with a +1/+1 counter on it
4. Resolve the Dominion Saboteur ability from step 1
5. Repeat

Results

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