Xavier Sal, Infested Captain + Animation Module + Thornbite Staff + Mana Cache

Xavier Sal, Infested Captain

Animation Module

Thornbite Staff

Mana Cache

How it works

1. Activate Xavier Sal's second ability by tapping it and sacrificing a creature.
2. When the creature dies, Xavier Sal triggers, untapping Xavier Sal.
3. Resolve the Xavier Sal ability from step 1, putting a +1/+1 counter on a creature you control and a charge counter on Mana Cache.
4. Animation Module triggers, holding priority, activate Mana Cache by removing a charge counter from it, adding C.
5. Resolve the Animation Module trigger, causing you to pay 1 to create a 1/1 Servo artifact creature token.
6. Repeat.
7. Once you have infinite +1/+1 counters among creatures you control, you may instead use Xavier Sal's first ability to get infinite copies of creature tokens you control.

This intricate loop turns Xavier Sal, Infested Captain into a relentless engine of growth and sacrifice, fueled by the persistent resource accumulation of Mana Cache to pay for Animation Module's triggered ability. As Xavier Sal sacrifices creatures to proliferate, the resulting death triggers untap it thanks to Thornbite Staff—which conveniently attaches itself automatically since Xavier Sal is a Shaman. Each proliferation adds counters that trigger Animation Module to churn out Servo tokens, which in turn feed Xavier Sal's sacrifice ability and keep the entire cascade rolling infinitely.