Anzrag, the Quake-Mole, and Arachnogenesis

Prerequisites

• Anzrag, the Quake-Mole on the battlefield
• Arachnogenesis in hand
• available

Steps

1. Activate Anzrag by paying , causing opponents to block Anzrag if able this turn
2. Cast Arachnogenesis by paying , preventing all damage being done this turn by non-Spider creatures
3. Declare Anzrag as an attacker, attacking an opponent who controls a creature but does not control a Spider
4. The opponent is forced to block Anzrag, triggering Anzrag, untapping all creatures you control and causing you to get an additional combat phase after this one
5. Any combat damage that would be dealt is prevented due to Arachnogenesis Repeat from step 3 each combat phase

Results

• Infinite combat phases
• Infinite untap of creatures you control
• Infinite mana creatures you control can produce