In the newest frame from the movie "Star Wars: The Rise of Skywalker" we can see the order "Knights of the Rhine" returning to the series
The new Star Wars installment brings back the Knights of Ren. A new look at Kylo Ren’s dark side faction features the latest frame from a movie published by Empire Magazine. The order introduced in “Star Wars: The Force Awakens” is known for sure that it is chaired by Kylo Ren, who murdered his master in “The Last Jedi” and took his position. None of the members of “Knight of Ren” except Kylo Ren appear in “Star Wars: The Last Jedi”. Their role in “The Rise of Skywalker” is so far shrouded in mystery. With the Son of Han Solo at its head, this order could prove to be more powerful than ever.
We also know about the Knights of Ren that, like their leader, they will stick to the dark side of the force . The group has been around for decades, and their activities take place outside of the highest order command structure. The commander led the order to destroy the new Jedi temple after he abandoned training there. The temple was then burned down and Luke Skywalker’s students were murdered.