Aggravated Assault, and Shriekwood Devourer

Prerequisites

• Aggravated Assault on the battlefield
• Shriekwood Devourer on the battlefield
• You control up to five lands that can tap to produce at least
• You control a creature with power 5 or greater that does not have summoning sickness, and that cannot be blocked and killed by an opponent

Steps

1. Declare any creature with power 5 or greater that cannot be blocked and killed by an opponent as an attacker
2. Shriekwood Devourer triggers, untapping at least five lands
3. Move to your postcombat main phase
4. Activate up to five lands by tapping them, adding at least
5. Activate Aggravated Assault by paying , untapping all creatures you control and causing you to get an additional combat and main phase after this one
6. Repeat

Results

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