Newly released concept art from Star Wars: The Rise of Skywalker showcases Sith Lords Revan, Malak, and Nihilus.
The newly concept art was revealed by Industrial Light & Magic and puts quite a bit of focus on Exegol and its Sith trappings.
Related: Graphic Artist Isatonic Imagines Keanu Reeves as Star Wars Character Revan!
The official twitter account teased the concept art on Twitter writing, “Just posted: Never-before-seen ILM Art Department concept art with commentary from Star Wars: The Rise of Skywalker, primarily from the film’s final act.”
The concept art begins by showcasing the Sith megastructure on Exegol and reveals the reasoning behind its design structure.
ILM reveals, “One suggestion for the structure’s silhouette was to mimic the Jedi Temple in Coruscant but flipped upside down to imply the opposing faction that is the Sith and their alignment to the Dark Side of the Force.”
Related: Rumor: Star Wars Developing Films Featuring Darth Malak
From there they reveal concept art of carvings and glyphs that they imagined would be found within the temple.
They explain the “Art Department referenced cultures like the Egyptians, Sumerians and Nabataeans as a basis for the ancient structure. Since the temple was exposed to the elements, concepts focused on erosion damage and aging to differentiate it from the other abandoned ruins.”
“Carvings, glyphs, and tributes were added to its weathered walls that represented the culture of the Sith,” they added.
It is in these carvings that we see Malak, Revan, and Nihilus.
You can see Malak in the bottom left of the right most image above. Revan is just to the right of him. Nihilus can be seen in the same column as Revan, but further up.
Nihilus would be showcased again when ILM revealed they “referenced images like the terracotta army found in China as a source of inspiration” for a “massive space filled with gigantic statues as far as they eye could see” that was located underneath the monolotih.
These statues would eventually be scrapped. ILM details, “As development progressed, the statues were simplified to achieve the ancient look production was pursuing. For the scale to work, the team explored various materials and processes to uncover how these sculptures might have been built.”
This concept art might explain rumors regarding films based on the Knights of the Old Republic or set in that time frame.
Back in September 2019, a rumor from We Got This Covered detailed that Lucasfilm was looking for a woman of color to play the lead role in movies based on Knights of the Old Republic.
That rumor also indicated that Wonder Woman director Patty Jenkins and A Wrinkle in Time director Ava DuVernay were on the short list to direct. We now know Jenkins is directing a Rogue Squadron film that is supposed to take place in a future era of Star Wars rather than in the past, where a Knights of the Old Republic set of films would take place.
Another rumor from May 2019 detailed that a Knights of the Old Republic script was actually being written by Alita: Battle Angel scribe Laeta Kalogridis.
That rumor came from BuzzFeed News and claimed that Kalogridis was “close to finishing the first script of a potential KOTOR trilogy.”
Related: Rumor: Game of Thrones Showrunners’ Star Wars Movie to Be Focused on Old Republic
Maybe the most prominent rumor about an Old Republic movie came from Star Wars Net in March 2019. They reported that Game of Thrones showrunners David Benioff and D.B. Weiss were supposed to adapt the Old Republic.
Star Wars News Net claimed the movie would be “set during the Old Republic, as Disney wants to open up the Star Wars timeline and appeal to a more ‘Game of Thrones’ style audience.”
In fact they claimed that filming was supposed to start in the latter half of 2019 and “art departments are in design phases now as the script is being finalized.”
Not only did they reveal concept art showing off Malak, Revan, and Nihilus, but they also revealed concept art of the new Sith Star Destroyers.
They explained that they based them off the original trilogy design but they were “retrofitted with a new cannon that would run along the underside of the hull.”
Along with the Sith Star Destroyers, they also featured designs from the Resistance forces flotilla revealing they “took vessels from previous films, games, comics and amusement parks in order to fill out the ranks.”
They also revealed they created a “plethora of new ships” as well. 
One of those ships, looks very similar to The Mandalorian’s Razor Crest. Although it is slimmed down and appears to be more of a fighter craft than the old gunship the Mandalorian used to pilot.
They also revealed that “many of the ships were kitbashed to create variations of the same model. Color was used to stylize the various models as well as livery and hull plating.”
Not only do we get designs, but they also feature art work of the two massive fleets in battle.
The inspiration for the massive battle were World War II conflicts like Pearl Harbor Midway.
ILM explains, “To create the battle, the artists referenced historical conflicts like Pearl Harbor and Midway. Footage from WWII military tactics were analyzed and interpreted to visualize the aerial clash between factions.”
They also went on to reveal that “first iterations of Exegol sported clear skies and a sunset light scheme. Finding this to be a less intimidating environment, the team did studies of skies, haze and clouds and atmosphere to amp the tension.”
You can see much more of the concept art on the ILM website including images of Bespin and Mustafar.
What do you make of the fact that concept art showcased Revan, Malak, and Nihilus?