Fain, the Broker, Thornbite Staff, Crystalline Crawler, and Gravecrawler

Prerequisites

• Fain, the Broker on the battlefield
• Thornbite Staff on the battlefield
• Crystalline Crawler on the battlefield
• Gravecrawler on the battlefield
• Thornbite Staff attached to Fain
• Fain does not have summoning sickness
• You control at least one additional Zombie

Steps

1. Activate Fain's first ability by tapping it and sacrificing Gravecrawler
2. Gravecrawler dies, triggering Fain, untapping it
3. Resolve the Fain ability from step 1, putting two +1/+1 counters on Crystalline Crawler
4. Activate Crystalline Crawler's first ability by removing a +1/+1 counter from it, adding
5. Cast Gravecrawler from your graveyard by paying
6. Repeat
7. Once you have infinite mana and counters, you may instead activate Fain's other abilities

Results

• Infinite +1/+1 counters
• Infinite colored mana
• Infinite creature tokens
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers
• Infinite Treasure tokens