Arcbound Reclaimer + Showdown of the Skalds + Elsha of the Infinite + Dark Sphere

Arcbound Reclaimer

Showdown of the Skalds

Elsha of the Infinite

Dark Sphere

How it works

1. Cast Dark Sphere either from your hand or from the top of your library by paying 0
2. Showdown of the Skalds and Elsha's prowess ability trigger.
3. Resolve the Showdown of the Skalds trigger, putting a +1/+1 counter on Arcbound Reclaimer.
4. Resolve the Elsha trigger, giving it +1/+1 until end of turn.
5. Activate Dark Sphere by tapping and sacrificing it.
6. Activate Arcbound Reclaimer by removing a +1/+1 counter from it, putting Dark Sphere from your graveyard onto the top of your library.
7. Repeat.