https://www.polygon.com/2018/9/24/17898072/destiny-2-forsaken-wishes-last-wish-raid

The Last Wish raid in Destiny 2: Forsaken is a little over a week old at this point. But in typical Destiny fashion, there are still plenty of secrets to discover. Late last week, players discovered that you can actually make wishes in the new raid. This can open up all sorts of doors — sometimes literally — or add fun, cosmetic effects to the game while you fight.

The wishing room is located just before the first fight in the raid: Kalli, the Corrupted. After some light jumping, you can climb your way into a small room filled with panels. Shooting these panels causes them to display one of the many different symbols used in the raid. If you manage to recreate a pattern that can be found on one of many wish plates scattered around the galaxy, and then step on a small panel inside the wishing room, you’ll activate the wish.