Pharaoh's Honor Guards are four giant statues found in the tomb underneath The Great Sphinx. They will remain inactive until the canopes are destroyed which will awaken them one by one.
The Honor Guards are big and tough Constructs, so don't rush in and destroy the shrines right away. They have no abilities but their basic attack hits all enemies in front of them. Take out a shrine, then destroy its associated statue and mummies, then repeat. Once all four statues have been eliminated, the doors to the room will open, allowing you to access the Hand of Balance for the main quest The Invocation.