Rat King, Verminister, Intruder Alarm, Belonging, and Shilgengar, Sire of Famine

Prerequisites

• Rat King, Verminister on the battlefield
• Intruder Alarm on the battlefield
• Belonging in hand
• Shilgengar, Sire of Famine on the battlefield
• available

Steps

1. Cast Belonging by paying
2. When Belonging enters, it and Intruder Alarm trigger
3. Resolve the Belonging trigger, creating three 1/1 Shapeshifter creature tokens with changeling
4. When the Shapeshifters enter, Intruder Alarm triggers three times
5. Resolve the Intruder Alarm triggers from this step and step 2, untapping all creatures four times
6. Activate Shilgengar by sacrificing Belonging
7. Activate Rat King by tapping it and sacrificing the Shapeshifters, returning Belonging from your graveyard to the battlefield
8. Repeat from step 2

Results

• Infinite Blood tokens
• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite mana creatures you control can produce
• Infinite sacrifice triggers
• Infinite untap of creatures