https://www.gamespot.com/articles/destiny-2-big-new-dlc-gets-a-name-and-cryptic-teas/1100-6459379/

Destiny 2's next expansion is called Forsaken, developer Bungie announced today. This was revealed in a new teaser video hyping up tomorrow's Year 2 reveal livestream.

The video shows Cayde-6 and a Guardian dropping onto what appears to be the Reef, which was Destiny 1's second social space and the home of the Awoken. The name Forsaken could be a reference to the Destiny character Mithrax, the Forsaken. Here's the teaser: