Yarus, Roar of the Old Gods, Cryptolith Rite, Obscuring Aether, and Ashnod's Altar

Prerequisites

• Yarus, Roar of the Old Gods on the battlefield
• Cryptolith Rite on the battlefield
• Obscuring Aether on the battlefield
• Ashnod's Altar on the battlefield
• available

Steps

1. Activate Obscuring Aether by paying , turning it face-down as a 2/2 creature
2. Activate Obscuring Aether by tapping it, adding
3. Activate Ashnod's Altar by sacrificing Obscuring Aether, adding
4. When Obscuring Aether dies, Yarus' second ability triggers, returning it from your graveyard to the battlefield face-down, then turning it face-up
5. Repeat

Results

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