Eternal Scourge, Young Deathclaws, Crystalline Crawler, Phyrexian Altar, and Doubling Season

Prerequisites

• Eternal Scourge in the graveyard
• Young Deathclaws on the battlefield
• Crystalline Crawler on the battlefield
• Phyrexian Altar on the battlefield
• Doubling Season on the battlefield
• available

Steps

1. Activate Eternal Scourge's scavenge ability, granted to it by Young Deathclaws, by paying and exiling Eternal Scourge from your graveyard, putting six +1/+1 counters on Crystalline Crawler due to Doubling Season
2. Activate Crystalline Crawler six times by removing six +1/+1 counters from it, adding
3. Cast Eternal Scourge from exile by paying
4. Activate Phyrexian Altar by sacrificing Eternal Scourge
5. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite colored mana
• Infinite death triggers
• Infinite sacrifice triggers
• Infinite storm count