Mortuary + Aetherflux Reservoir + Phantom Train + Gwenom, Remorseless

Mortuary

Aetherflux Reservoir

Phantom Train

Gwenom, Remorseless

How it works

1. Activate Phantom Train by sacrificing a creature
2. When the creature dies, Mortuary triggers, putting the creature from your graveyard onto the top of your library.
3. Resolve the Phantom Train ability.
4. Cast the creature from the top of your library by paying X life, where X is the creature's mana value.
5. Aetherflux Reservoir triggers, causing you to gain 1 life for each spell you've cast this turn.
6. Repeat.

This loop turns a simple sacrifice into an engine of endless iteration by using Mortuary to recycle your fallen creatures straight back to the top of your library whenever they hit the graveyard. Gwenom, Remorseless then steps in to let you play those creatures directly from the top of your library, bypassing their mana costs by paying life instead—a cost easily offset because Gwenom, Remorseless also boasts lifelink and feeds the life-gaining engine of Aetherflux Reservoir. As you repeatedly cast and sacrifice your creatures to fuel Phantom Train, Aetherflux Reservoir ramps up its storm count with every iteration until you can finally cash in all that accumulated life to fire off a lethal 50-damage blast at any target.