Choke + Harbinger of the Seas

GU identity

Commander legal

The 2 combo pieces

• Choke
• Harbinger of the Seas

How to execute it

1. Because Harbinger of the Seas causes all nonbasic lands to be Islands, and Choke prevents Islands from untapping during their controller's untap steps, nonbasic lands do not untap during their controller's untap steps.

What the combo produces

• Lock
• Mass Land Denial
• Nonbasic lands do not untap