Druid's Call, Intruder Alarm, and Viridian Longbow

Prerequisites

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

Steps

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

Results

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