Iridescent Drake, Necrogen Communion, and Ashnod's Altar

Prerequisites

• Iridescent Drake on the battlefield
• Necrogen Communion on the battlefield
• Ashnod's Altar on the battlefield
• Necrogen Communion attached to Iridescent Drake

Steps

1. Activate Ashnod's Altar by sacrificing Iridescent Drake, adding
2. When Iridescent Drake dies, Necrogen Communion triggers, returning Iridescent Drake from your graveyard to the battlefield
3. When Iridescent Drake enters the battlefield, it triggers, returning Necrogen Communion from your graveyard to the battlefield attached to Iridescent Drake
4. Repeat

Results

• Infinite colorless mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers