The Heart of Darkness is a point of interest that I created for Battle for Azeroth where you can find the Underrot dungeon entrance and the Uldir raid entrance.
"It was a titan research and quarantine facility, which houses something that could potentially wipe out all life on the planet. When the titans were conducting experiments on the Old Gods and dissecting them to try to understand them, they ended up creating the blood god G'huun. He was locked away within Uldir via three seals but now only one seal remains. The three seals are disks located within the pyramids of Dazar'alor, Atul'Aman, and Nazwatha."