Cauldron of Souls + Dross Scorpion + Krark-Clan Ironworks + Encroaching Mycosynth

Cauldron of Souls

Dross Scorpion

Krark-Clan Ironworks

Encroaching Mycosynth

How it works

1. Activate Cauldron of Souls by tapping it, giving the creature with bloodthirst persist until end of turn.
2. Activate Krark-Clan Ironworks by sacrificing the creature with bloodthirst, adding CC.
3. When the creature dies, its persist ability and Dross Scorpion trigger.
4. Resolve the persist trigger, returning the creature from your graveyard to the battlefield, which enters the battlefield with at least one +1/+1 counter on it due to its bloodthirst ability.
5. Resolve the Dross Scorpion trigger, untapping Cauldron of Souls.
6. Repeat.

This intricate loop transforms a humble creature into an endless engine of sacrifice and rebirth, fueled by the mana-generating prowess of Krark-Clan Ironworks. Encroaching Mycosynth is the glue that holds the machinery together, turning all your nonland permanents into artifacts so that Dross Scorpion can watch over your entire board and untap Cauldron of Souls whenever anything falls. With the Cauldron granting persist, your creature can die and return to the battlefield—its entering with a -1/-1 counter neatly neutralized by the +1/+1 counters from its bloodthirst ability—allowing you to sacrifice it over and over again to net infinite colorless mana along with an endless stream of death, sacrifice, and ETB triggers.