- This article is about an in-universe event. For the in-game mission, see Unexpected Visitor.
Operation Sighthound was an Osean operation during the Lighthouse War to capture the Erusean Royal Navy's advanced nuclear submarine, the Alicorn, while it was docked at Artiglio Port. The Osean Air Defense Force's Brigadier General Howard Clemens led the operation.
Clemens sent the Long Range Strategic Strike Group (LRSSG)'s Strider Squadron, supported by Drake and Enchanter Squadrons, to secure air superiority. Clemens also sent a detachment of OMDF vessels, led by the landing ship Puffin, to land at Artiglio and capture the Alicorn. OIA weapons analyst David North provided intelligence on the Alicorn to the LRSSG.
Despite a change in the operation time and a surprise appearance by Mimic Squadron, Osea's pilots obtained air superiority, but the Alicorn abandoned its Erusean allegiance and began acting independently. Alicorn Captain Matias Torres ordered the submarine to fire and sink all Osean ships, launched a squadron of aircraft carrying a cruise missile, and escaped the area. Strider Squadron's flight lead, Trigger, shot down the aircraft carrying the cruise missile.
After losing the Njord Fleet, an Arsenal Bird, and an IRBM base, Erusea was running out of options to stop Osea's counteroffensive. To cover the deficit in its forces, Erusea officially commissioned the Alicorn on August 11 and sent it to Artiglio; it arrived on September 4.
Clemens and OIA analyst David North approached the Long Range Strategic Strike Group on September 4th with a mission - to capture the Alicorn, and seize its weapons of mass destruction in order to gain an advantage in postwar peace negotiations. The plan was for allied squadrons, an ESM team, codename "Enchanter", and an OMDF landing fleet to sortie at Artiglio, defeat the Erusean forces, and capture the sub without damaging it.
- "Heed my words! This boat has the means to end this hideous war, in a definitive and elegant manner. We seek not a conflict but rather a restoration of balance, a judgment. And it will be done with reason, from beginning to end. The world shall be horrified by the number of lives we will take. Only then will they let go of their weapons, weapons that would have taken the lives of ten million."
- ― Capt. Matias Torres
The ESM craft and friendly squadrons arrived late to the operation, with Strider Squadron having to battle dozens of Erusean aircraft on their own.
As the friendly aircraft arrived, the Eruseans began launching anti-ship aircraft to destroy the landing fleet, but Trigger defended the fleet successfully.
At that moment, two mysterious Su-47 Berkuts sporting Osean markings appeared, downing an Erusean aircraft and furiously engaging Trigger in a dogfight. After a quick engagement, the two aircraft, call signs Scream and Rage, retreated from the airspace, promising "Three Strikes" that they would kill him the next time they met.
As the fleet approached the port area, Erusean HQ officers ordered Alicorn captain Matias Torres to scuttle the sub to prevent the Oseans obtaining it. In spite of these orders, Torres rebelled, declaring that the Alicorn no longer belonged to the Erusean Navy, and set sail, utterly crippling the flagship Puffin with one shot from its railguns and the rest of the landing fleet with anti-ship missiles that the destroyers and cruisers' CIWS were unable to shoot down in time. A detachment of Rafale Ms from the Alicorn took off from the sub, with a WMD cruise missile in tow. The squadron attempted to flee the airspace with the WMD under order from Torres, but all aircraft were shot down by Trigger, eliciting anger from the captain, who vowed vengeance against "Three Strikes". In the confusion and scramble to shoot down the Rafales, however, the Alicorn submerged and quickly fled the area.