The Crows of Antiva may be the most famous and most expensive of Thedas's assassins, but they are not the most active. That dubious honor belongs to the Shadows of the Emperor, the personal cadre of killers employed by the throne of Orlais. This armor was made for use by the Shadows whenever the Grand Game should wander out of hand.
—From Codex entry: Shadow of the EmpireThe Shadow of the Empire is a fairly good armor, suitable for rogues. It is bought from Legnar in Orzammar Commons and buying it unlocks the Codex entry: Shadow of the Empire.
Can also be bought from The Crown and Lion in Dragon Age: Origins - Awakening
Possibly a reference to Shadows of the Empire.