Dawnsire, Sunstar Dreadnought, Vigor, Crystalline Crawler, and Hellkite Charger

Prerequisites

• Dawnsire, Sunstar Dreadnought on the battlefield
• Vigor on the battlefield
• Crystalline Crawler on the battlefield
• Hellkite Charger on the battlefield

Steps

1. Declare Hellkite Charger as an attacker, triggering it and Dawnsire
2. Resolve the Dawnsire trigger, attempting to deal 100 damage to Crystalline Crawler, which will result in 100 +1/+1 counters being placed on it instead due to Vigor
3. Holding priority, activate Crystalline Crawler's first ability seven times by removing seven +1/+1 counters from it, adding
4. Resolve the Hellkite Charger trigger, causing you to pay to untap all attacking creatures you control and to get an additional combat phase after this one
5. Repeat each combat phase

Results

• Infinite colored mana
• Infinite combat phases
• Infinite untap of creatures you control
• Infinite mana creatures you control can produce
• Infinite +1/+1 counters