As the Jade Brotherhood discovers a new side to the jade crystals, a mysterious condition threatens the hard-won stability of Cantha. Rejoin your Friends' Detective Agency allies - Detective Rama, Xunlai Jade Yao, and Gorrik - to investigate the dangers lurking in the depths of the Jade Sea and find the source of the corruption of the jade mine workers. “What Lies Beneath” is a new chapter of End of Dragons, immediately available for free for all players who already own the expansion. Explore a new story and the new map Gyala Delve, and get new rewards starting today! Unlike previous Living World releases, it can be unlocked at any time at no gem cost.
https://www.guildwars2.com/en/news/continue-the-guild-wars-2-end-of-dragons-story-today-in-what-lies-beneath/