Light of Day, Darkest Hour, and Alchor's Tomb

Prerequisites

• Light of Day on the battlefield
• Darkest Hour on the battlefield
• Alchor's Tomb on the battlefield
• available

Steps

1. All creatures are black, and black creatures are unable to attack or block
2. Alchor's Tomb is capable of making your creatures permanently nonblack, allowing you bypass said restriction

Results

• Creatures cannot attack or block
• Opponents can't attack or block