Adarkar Valkyrie + Intruder Alarm + Altered Ego

Adarkar Valkyrie

Intruder Alarm

Altered Ego

How it works

1. Activate Adarkar Valkyrie by tapping it, targeting any legendary creature you control.
2. Cast Altered Ego by paying 2, choosing to have it enter the battlefield as a copy of the legendary creature targeted in step 1.
3. Put the legendary creature into your graveyard due to the legend rule.
4. Adarkar Valkyrie and Intruder Alarm trigger.
5. Resolve the Intruder Alarm trigger, untapping all creatures.
6. Holding priority, activate Adarkar Valkyrie by tapping it, targeting Altered Ego.
7. Resolve the Adarkar Valkyrie trigger from step 4, returning the legendary creature to the battlefield from your graveyard.
8. Put Altered Ego into your graveyard due to the legend rule.
9. Adarkar Valkyrie and Intruder Alarm trigger.
10. Resolve the Intruder Alarm trigger, untapping all creatures.
11. Holding priority, activate Adarkar Valkyrie by tapping it, targeting the legendary creature.
12. Resolve the Adarkar Valkyrie trigger from step 9, returning Altered Ego to the battlefield from your graveyard as a copy of the legendary creature.
13. Repeat from step 3.

This ingenious loop plays out like a theatrical relay, using the legend rule as both the catalyst for destruction and the engine for rebirth. By copying your legendary creature with Altered Ego, the game's state-based actions force one into the graveyard, which immediately triggers Adarkar Valkyrie's delayed return effect while simultaneously waking up the entire board through Intruder Alarm's static untap ability. Because Intruder Alarm untaps Adarkar Valkyrie fresh off every single creature entry, you can continuously ping back and forth—resurrecting the original legend and Altered Ego interchangeably—to harvest endless enter-the-battlefield triggers and tap effects from any creatures you control.