Reaper King + Kozilek, Butcher of Truth + Atla Palani, Nest Tender + Maskwood Nexus

Reaper King

Kozilek, Butcher of Truth

Atla Palani, Nest Tender

Maskwood Nexus

How it works

1. Cause a creature to enter the battlefield under your control by any method.
2. When that creature enters the battlefield, Reaper King triggers, destroying that creature.
3. Resolve Atla Palani's trigger, revealing cards from the top of your library until you reveal a creature card and putting it onto the battlefield.
4. Repeat from step 2 until Kozilek enters the battlefield then dies, or until you choose to end the loop by destroying an opponent's permanent.
5. If Kozilek dies, it and Atla Palani trigger.
6. Resolve Kozilek's trigger, shuffling your graveyard into your library.
7. Continue from step 3.

This looping engine relies on Maskwood Nexus to turn every creature you control and own into a Scarecrow and an Egg simultaneously, allowing them to synergize with Atla Palani, Nest Tender and Reaper King in devastating fashion. Once you trigger the chain, Reaper King destroys the newly entering creature, which immediately causes Atla Palani to flip the top of your library into another creature. If you happen to hit Kozilek, Butcher of Truth, its graveyard trigger ensures you never run out of library to flip through, creating a self-sustaining loop that continually spits out permanents to blow up with Reaper King.