World Shaper + Glacial Chasm + Mortuary Mire + Phantom Train

World Shaper

Glacial Chasm

Mortuary Mire

Phantom Train

How it works

1. While Glacial Chasm is on the battlefield, all damage that would be dealt to you is prevented.
2. At the beginning of your upkeep, Glacial Chasm triggers. Choose not to pay its cumulative upkeep cost and sacrifice it.
3. Activate Phantom Train by sacrificing World Shaper.
4. When World Shaper dies, its second ability triggers, returning Glacial Chasm and Mortuary Mire from your graveyard to the battlefield tapped.
5. When Glacial Chasm and Mortuary Mire enter, they each trigger.
6. Resolve the Glacial Chasm trigger, sacrificing Mortuary Mire.
7. Resolve the Mortuary Mire trigger, putting World Shaper from your graveyard onto the top of your library.
8. Resolve the Phantom Train ability from step 3.
9. Move to your next turn, drawing World Shaper during your draw step.
10. At the beginning of your upkeep, Glacial Chasm triggers. Choose not to pay its cumulative upkeep cost and sacrifice it.
11. Cast World Shaper by paying 3.
12. Repeat from step 3.

This clever loop lets you completely lock out any damage dealt to you by hiding behind the impenetrable safety of Glacial Chasm every single turn. By sacrificing World Shaper to fuel Phantom Train's ability, you trigger World Shaper's death ability to resurrect both Glacial Chasm and Mortuary Mire simultaneously from your graveyard. Mortuary Mire then effortlessly fishes World Shaper back to the top of your library so you can redraw and recast it, ensuring the cycle repeats indefinitely without ever paying the Chasm's growing cumulative upkeep.