Animation Module + Scion of the Swarm + Ashnod's Altar + Dross Harvester

Animation Module

Scion of the Swarm

Ashnod's Altar

Dross Harvester

How it works

1. Activate Ashnod's Altar by sacrificing another creature, adding CC.
2. When the creature dies, Dross Harverster's second ability triggers, causing you to gain 2 life.
3. Scion of the Swarm triggers, putting a +1/+1 counter on itself.
4. Animation Module triggers, causing you to pay 1 to create a 1/1 Servo artifact creature token.
5. Repeat.

This clever loop turns the life-draining drawback of Dross Harvester into a perpetual engine by pairing its death-triggered life gain with Scion of the Swarm, which grows larger every time that life is gained. Because Scion of the Swarm receives a +1/+1 counter, Animation Module triggers to let you pay a single mana and forge a 1/1 Servo artifact creature token. You can then feed that newly created token right into Ashnod's Altar, sacrificing it to generate the two colorless mana needed to pay the Animation Module's fee while netting an extra mana in the process. Dross Harvester helps offset its own upkeep life loss through these deaths, ultimately fueling an unstoppable cascade of infinite sacrifice, mana, and growth.