The Codex internet credited another userSynth Potatofor providing them the images, also since removed following aDMCA notice.
However, they’d already been shared earlier by Rainbow Six leakerScriptLeaksR6.
The Codex Networks tweet claimed that the artwork was taken from the Ubisoft Store.

More shadows of what seem to be people with raised weapons appear further down.
Ireportedon the rumours surrounding the next Assassins Creed earlier this week.
Giant Bombs Jeff Grubb also waded in to back up the Mirage name claim.

If the appropriately titled Assassins Creed: Mirage really exists then its tipped to see release in spring 2023.
Ill keep you updated.