The Crowns fought bravely, but knowing about A'Tor's massive victories at sea against the Forebears, Emperor Tiber Septim sent Admiral Richton, his best naval commander, with the biggest Imperial fleet to lay waste to the Crown Navy. The ships lined up and then charged into the gaps between the enemy ships. Prince A'Tor seeing Admiral Richton's flagship, Dragon, alone behind his lines turned his ship around and ordered his archers to fire at the ship with flaming arrows, but himself was shot by Richton's assassin, with a poisoned arrow. A'Tor's mages attempted to save A'Tor and the fleet but they were surrounded, outmanned, and outgunned by the Imperial forces.
The dragon Nafaalilargus also played a role in the Battle of Hunding Bay after being called on as a mercenary by Tiber Septim. The dragon sank Prince A'tor's ship with a single fiery breath after the prince had been struck down by a poisoned arrow, destroying all hope of A'tor's wizard removing the poison.This effectivley won the battle for the Empire.
With the defeat of the Crowns, Hammerfell was incorporated into the Empire as a province and Admiral Richton was made the Provisional Governor of Stros M'Kai. Nafaalilargus was then put under the command of Lord Amiel Richton. He was then assigned to guard the soul gem of Prince A'tor, in the treasuries beneath the island's palace. The dragon was slain in 2E 864 by Cyrus the Redguard, who then stole back the soul gem. His death weakened the Imperial presence on the island considerably. However, due to the nature of dragons, Nafaalilargus isn't truly dead and could be raised again.