Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight, Ashnod's Altar, and Arcbound Lancer

Prerequisites

• Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight on the battlefield
• Ashnod's Altar on the battlefield
• Arcbound Lancer on the battlefield

Steps

1. Activate Ashnod's Altar by sacrificing Arcbound Lancer
2. When Arcbound Lancer dies, its modular ability and persist ability trigger
3. Resolve the modular trigger, putting Arcbound Lancer's +1/+1 counters on another artifact creature
4. Resolve the persist trigger, returning Arcbound Lancer from your graveyard to the battlefield
5. It will not have a -1/-1 counter on it due to its modular ability
6. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite colorless mana
• Infinite +1/+1 counters on artifact creatures you control