Druid's Call, Intruder Alarm, and Lightning Prowess

Prerequisites

• Druid's Call on the battlefield
• Intruder Alarm on the battlefield
• Lightning Prowess on the battlefield
• Druid's Call and Lightning Prowess attached to an indestructible creature you control that does not have summoning sickness

Steps

1. Activate the creature with Druid's Call and Lightning Prowess attached by tapping it, dealing 1 damage to itself
2. Druid's Call triggers, creating a 1/1 Squirrel creature token
3. When the Squirrel enters the battlefield, Intruder Alarm triggers, untapping all creatures
4. Repeat

Results

• Infinite creature tokens
• Infinite ETB
• Infinite mana creatures you control can produce
• Infinite untap of creatures you control