Thran Vigil, Benthic Biomancer, and Grave-Shell Scarab

Prerequisites

• Thran Vigil on the battlefield
• Benthic Biomancer on the battlefield
• Grave-Shell Scarab in hand

Steps

1. Put a +1/+1 counter on Benthic Biomancer
2. Benthic Biomancer triggers, causing you to mill a card and return Grave-Shell Scarab from your graveyard to your hand, and then causing you to discard Grave-Shell Scarab
3. Thran Vigil triggers, putting a +1/+1 counter on Benthic Biomancer
4. Repeat from step 2

Results

• Infinite self-mill