Crackdown Construct, and Demonspine Whip

Prerequisites

• Crackdown Construct on the battlefield
• Demonspine Whip on the battlefield
• Demonspine Whip attached to any creature you control

Steps

1. Activate Demonspine Whip by paying
2. Crackdown Construct triggers, giving itself +1/+1 until end of turn
3. Repeat

Results

• Infinitely large Crackdown Construct until end of turn