The USS Vengeance attacks

Captain Sulu took the USS Excelsior near the Klingon border when the moon Praxis exploded. The explosion created a temporal vortex in which the USS Vengeance, a Federation warship with a jet black hull, emerged! The Vengeance was from the alternate reality and was designed by John Harrison (also known as Khan Noonien Singh) and was commanded by the evil Admiral Alexander Marcus. The Klingons attacked the Vengeance with 3 K'Tinga-class battle cruisers and she destroyed all 3 but suffered bad damage. Sulu reported the incident to Starfleet, which sent the entire Federation First Fleet to intercept the Vengeance. A fierce battle ensued in which 6 Federation starships were destroyed and another 10 suffered bad damage. The Vengeance was not so lucky. She was destroyed with all hands lost, including Admiral Marcus.