First reported by Insider Gaming, a 4chan user shared assets purportedly from the 2021 CD Projekt hack.

In the initial post, these images were of cancelled DLC that was supposed to happen during a new "corporate war" and compared its scope to the "Blood and Wine" expansion for The Witcher 3. While I would take this interpretation and the source of the image with a grain of salt, I believe the image is legitimate because of the extent of the area shown, including an out-of-bounds view of one area that includes a cyberpunk HUD. [The parent file is "02_moon" and contains folders such as "arisaka_lab", "cosmodrome", and "bomb_crater_set". According to a mock-up of the map, the lunar area will be 6 square kilometers, or about a quarter of the size of the base game map, with areas such as the "NC (Night City?) base," "HR residence," and an attractive "drug lab."

The most exciting map features relate to the bomb_crater_set file." The "Exterior Movie Set" seems to be the perfect staging area for a Holy Weed/Brindance-focused side quest, such as Sinnerman, the centerpiece of the base game. The thread also includes prototype building and area designs, one of the most embodied models of which appears to be one of the mass drivers from cyberpunk lore.

Whatever the area was intended to be, it must not have been very well developed. Aside from the fragmentary assets on display, the CD Projekt hack allegedly occurred in February 2021, shortly after the launch of the base game. The thread also includes two images of what appears to be an early version of Phantom Liberty's Dogtown.

The Moon Colony and the various shenanigans of the corporations there feature particularly heavily in cyberpunk lore and 2077 stories. Characters in the cartoons "Edge Runner" and "Phantom Liberty" are eager to escape from it; in "Corp," V assassinates a member of the European Space Agency, and in the endings of "Star" and "(Fear Not) Reaper," V commits a robbery at a satellite casino. The development toward the stars has been a frequent topic of cyberpunk DLC and possible sequels.

Late last year, Igor Sarzynski, scenario director at CD Projekt Red, said that the team never considered setting the Cyberpunk 2077 DLC after the ending of the base game. If these files are legitimate (and they seem to be), it would be an interesting peek behind the curtain of cyberpunk development, but I don't think the Sick Moon expansion is anything to lament, and what we got with Phantom Liberty was pretty epic.