Cloakwood Swarmkeeper, Animation Module, and Phyrexian Altar

Prerequisites

• Cloakwood Swarmkeeper on the battlefield
• Animation Module on the battlefield
• Phyrexian Altar on the battlefield
• You have a way to cause a token to enter the battlefield under your control

Steps

1. Cause a token to enter the battlefield under your control
2. The token enters the battlefield, triggering Cloakwood Swarmkeeper, putting a +1/+1 counter on Cloakwood Swarmkeeper
3. Animation Module triggers
4. Holding priority, activate Phyrexian Altar by sacrificing the token, adding
5. Resolve the Animation Module trigger, causing you to pay to create a 1/1 Servo artifact creature token
6. Repeat from step 2

Results

• Infinite +1/+1 counters on Cloakwood Swarmkeeper
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers