Tale of Katara and Toph + Animation Module + Yarus, Roar of the Old Gods + Insidious Roots

Tale of Katara and Toph

Animation Module

Yarus, Roar of the Old Gods

Insidious Roots

How it works

1. Activate an artifact creature token by tapping it, adding 1.
2. The creature's ability granted to it by Tale of Katara and Toph triggers, putting a +1/+1 counter on the creature.
3. Animation Module triggers, causing you to pay 1 to create a 1/1 Servo artifact creature token.
4. Repeat.