Adarkar Valkyrie, Intruder Alarm, and Composite Golem

Prerequisites

• Adarkar Valkyrie on the battlefield
• Intruder Alarm on the battlefield
• Composite Golem on the battlefield
• Adarkar Valkyrie does not have summoning sickness

Steps

1. Activate Adarkar Valkyrie by tapping it, targeting Composite Golem
2. Activate Composite Golem by sacrificing it, adding
3. Composite Golem dies, triggering Adarkar Valkyrie, returning Composite Golem from your graveyard to the battlefield
4. Composite Golem enters the battlefield, triggering Intruder Alarm, untapping all creatures
5. Repeat

Results

• Infinite colored mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mana creatures you control can produce
• Infinite sacrifice triggers
• Infinite untap of all creatures