Rat King, Verminister, Thornbite Staff, Belonging, and Ashnod's Altar

Prerequisites

• Rat King, Verminister on the battlefield
• Thornbite Staff on the battlefield
• Belonging in hand
• Ashnod's Altar on the battlefield
• available

Steps

1. Cast Belonging by paying
2. When Belonging enters, it triggers, creating three 1/1 Shapeshifter creature tokens with changeling
3. Activate Ashnod's Altar by sacrificing Belonging
4. When Belonging dies, Rat King triggers, untapping Rat King
5. Activate Rat King by tapping it and sacrificing the Shapeshifters
6. When the Shapeshifters die, Rat King triggers three times, untapping Rat King
7. Resolve the Rat King ability from step 5, returning Belonging from your graveyard to the battlefield
8. Repeat from step 2

Results

• Infinite ETB
• Infinite LTB
• Infinite colorless mana
• Infinite death triggers
• Infinite sacrifice triggers