Xavier Sal, Infested Captain, Experiment Kraj, Devoted Druid, and Tidewater Minion

Prerequisites

• Xavier Sal, Infested Captain on the battlefield
• Experiment Kraj on the battlefield
• Devoted Druid on the battlefield
• Tidewater Minion on the battlefield
• Experiment Kraj and Xavier Sal do not have summoning sickness
• Devoted Druid and Tidewater Minion each have at least one +1/+1 counter on them
• You control at least one creature token

Steps

1. Activate Experiment Kraj using Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it
2. Activate Xavier Sal's first ability by tapping it and removing a -1/-1 counter from Experiment Kraj, creating a copy of any creature token you control
3. Activate Experiment Kraj using Tidewater Minion's second ability by tapping it, untapping Xavier Sal
4. Repeat

Results

• Infinite copies of creature tokens you control
• Infinite creature tokens
• Infinite ETB