Arenanet has released a new teaser video for Revenge of the Capricorn, the PvP map is part of the Guildwars 2 Living World Season 3 update that was announced two weeks ago.
Revenge of the Capricorn is an old map that was scrapped from the game a few years ago. The map has been repurposed as Player versus Player map and will be added to the game on July 26th.
In the original map players had to fight underwater in order to advance. In the new version underwater combat has been removed and pirate ships and NPCs have been added.