Animation Module + Securitron Squadron + Thermopod

Animation Module

Securitron Squadron

Thermopod

How it works

1. Put a +1/+1 counter on a creature you control.
2. Animation Module triggers, causing you to pay 1 to create a 1/1 Servo artifact creature token.
3. When the Servo enters the battlefield, Securitron Squadron triggers, putting a +1/+1 counter on the Servo.
4. Animation Module triggers, holding priority, activate Thermopod's second ability by sacrificing the Servo, adding .
5. Resolve the Animation Module trigger, causing you to pay 1 to create a 1/1 Servo artifact creature token.
6. Repeat from step 3.