Metastatic Evangel + Evolution Witness + Hangarback Walker

Metastatic Evangel

Evolution Witness

Hangarback Walker

How it works

1. Cast Hangarback Walker by paying 0.
2. Hangarback Walker enters and dies as a state-based action due to having 0 toughness.
3. Metastatic Evangel triggers, causing you to proliferate and put a +1/+1 counter on Evolution Witness.
4. Evolution Witness triggers, returning Hangarback Walker from your graveyard to your hand.
5. Repeat.

This ingenious loop uses Hangarback Walker cast for zero mana as a disposable trigger piece that immediately heads to the graveyard, where Evolution Witness is waiting to fish it right back out. Every time Hangarback Walker enters and perishes, Metastatic Evangel triggers its proliferate ability to add a counter to Evolution Witness. That single added counter triggers Evolution Witness to return Hangarback Walker to your hand, perfectly resetting the loop to generate endless enters-the-battlefield, death, and proliferate triggers.