Grimgrin, Corpse-Born + Gravecrawler + Song of Freyalise

Grimgrin, Corpse-Born

Gravecrawler

Song of Freyalise

How it works

1. Activate Grimgrin by tapping it, adding .
2. Activate Grimgrin by sacrificing Gravecrawler, untapping Grimgrin and putting a +1/+1 counter on it.
3. Cast Gravecrawler from your graveyard by paying .
4. Repeat.

This recursive engine turns the graveyard into a relentless workshop by leveraging Song of Freyalise's first two chapters, which temporarily grant all your creatures the ability to tap for any color of mana. This allows Grimgrin, Corpse-Born to tap itself for the black mana needed to feed Gravecrawler's recursive casting cost. By sacrificing Gravecrawler to Grimgrin's ability, you not only fuel the loop and generate infinite death triggers, but also steadily grow Grimgrin into an unstoppable behemoth with endless +1/+1 counters.