Evasive Maneuver Chel-Akep was a Romulan starship tactic. When a vessel is been pursued by an enemy vessel it cloaks, changes its course and launches a probe. The probe emits an energy signature that matches that of the ship but with a slight flaw in its cloaking device so to be detectable. The hostile vessel pursues the probe while the Romulan vessel makes good its escape or circles around to strike at the vessel. (The Dominion War Sourcebook: The Fires of Armageddon)