TL;DR:Alliance ship and Horde ship exchange ambassadors. Both sides intended to take the ambassadors hostage all along and open fire on the opposite ship. Human captain lies and says the Horde ambassador attacked him. The Horde ambassador is a Tauren Druid who had previously worked with Night Elf Druids that happened to be on the ship at Mount Hyjal against Ragnaros under Malfurion. The Night Elf Druids don't believe the Human captain and save the Tauren Druid who escapes into the ocean in Aquatic Form. Human captain tries to kill one of the Night Elf Druids for treason. Night Elf Druid's sister cuts the Human captain's throat first. Both Alliance and Horde ships go down in the fight. Dwarven Ambassador and his sister manage to get off the Horde ship and ends up with the Night Elves. Tauren Druid comes back to heal them.