Intruder Alarm, Maskwood Nexus, and Myr Welder

Prerequisites

• Intruder Alarm on the battlefield
• Maskwood Nexus in exile
• Myr Welder on the battlefield
• Creatures you control can tap to produce at least

Steps

1. Activate any number of mana-producing creatures you control by tapping them, adding at least
2. Activate Myr Welder using Maskwood Nexus's ability by paying and tapping it, creating a 2/2 Shapeshifter creature token
3. When the Shapeshifter enters the battlefield, Intruder Alarm triggers, untapping all creatures
4. Repeat from step 2
5. If creatures you control can tap to produce at least , this combo nets infinite mana

Results

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