I bet it involves shooting guns.
Key art showing Guardians and the main baddy from Destiny 2: The Final Shape.

Bungie announced that they will hold a Developer Gameplay Preview for Destiny 2: The Final Shape on April 9 at 9:30 AM (PT). You will be able to watch through Bungie's Twitch channel or through YouTube.

This new preview will offer fans more information on the upcoming Destiny 2 expansion, The Final Shape. In The Final Shape, players will go after the Witness through the Pale Heart of the Traveler, rally the Vanguard, and seek to end the War of Light and Darkness.

Related, there was another stream that went live today for Destiny 2: Into the Light. Into the Light being an upcoming two-month content update that kicks off on April 9th. Today's video was the third and final stream for developer previews. Each video showed off new content, such as the wave-based Onslaught mode, some returning weapons, limited-edition ornaments, Hall of Champions social space, two reprised Exotic missions, and more. Into the Light will be free to all players.

The third and final preview stream for Into the Light can be found below.