The Battle of Port Sea was the fifth and final battle of the Chaos War, fought on 7 Aut'mo', LY 912. It took place in Port Sea, about 400 miles southeast of Near Port. Before a truce was called, the Navy of the Second Order lost 1 Destroyer, 1 Dreadnought, 2 Galleons, and 2 Frigates. Rebel forces commanded by Alphonse Teach lost 1 Galleon, 4 Frigates, and 2 Corvettes. A naval Cruiser which had been commandeered during the Second Battle of East Port was later returned to the fleet of Ship. A Galleon which had been commandeered from that fleet, as well as a Frigate commandeered from the fleet of Olek, were among the ships Teach lost during the battle. However, a Dreadnought that had been commandeered from Olek was retained by the rebels after the war, eventually becoming part of the Chaos Navy.
On 5 Aut'gin, Teach's fleet departed Shanty, transporting civilian recruits to Shipsister. on 8 Aut'gin, the fleet fought a brief skirmish, the Battle of West Ocean. At that time, they were joined by a fleet commanded by Yoshi Des'Yoshi, from Woodstockade. They continued on to Shipsister, where they arrived on 14 Aut'gin. That day, they rendezvoused with a task force led by Earl Prowess, which had departed Tanq on 9 Aut'gin, also transporting recruits. The combined fleet now totaled 14 ships. They continued on toward Port, the headquarters of the Navy, with little or no real hope of victory.
Following the Battles of East Ports on 22 Aut'gin, a fleet commanded by Gregory deCamp also began sailing toward Port. That fleet consisted of 10 ships. They rendezvoused with Teach's fleet on 1 Aut'mo'. The 24 ships continued toward Port together, still having little (but not nonexistent) hope of victory. On 2 Aut'mo', deCamp received intelligence from a spy working for Stavros Supprus in Port. (Supprus was at that time a prisoner of the Army in Near Port.) The spy informed deCamp that 13 ships had departed Port the day before, en route to Near Port, to help transport Army troops to First Village. A few days earlier, troops commanded by Alecstar Inco had defeated forces loyal to the Second Order, but King Demos Royal (who had fled to Near Port with his Sorreter/personal guard, René Deadzone) ordered General Tovan Middlebury to retake the village. When deCamp passed this information on to Teach and Inco, it led to a debate between the two about whether to continue with the original plan of attacking Port, which now seemed far more likely to end in success, or to change course and head to Near Port. Inco hoped to blockade the naval fleet from transporting troops, a task which Teach said would prove impossible, especially considering Near Port would be sending ships of its own, and ships from both Ship and Ristar couldn't be far behind Teach's fleet. Ultimately, Teach gave in to Inco's wishes.
All the various fleets (Teach's 24 ships vs. 13 from Port, 5 from Near Port, 5 from Ship, and 3 from Ristar) finally met on the morning of 7 Aut'mo', and battle commenced. However, after a few hours, Col. Cynthia Grandview delivered shocking new information to both Gen. Middlebury and Admiral Althis Portman, proving numerous illegal activities in which The Cabal had engaged over the years, most notably framing the Protestant Movement for the Laser Plot of 904. This led to the general and admiral deciding they could no longer support the Cabal. They both ordered their troops to stand down, on both land and sea. While there were a few soldiers (notably Col. Charles Woodman of Near Port and James Major of Port) who refused to obey this command, the majority did, and the war was soon declared officially over.