The Outlast Trials from Red Barrels has a huge new update out now that brings in a PvP invasion mode, and there's also now anti-cheat added into the game.
In the new Invasion Mode players can join your game as either a Reagent or an Imposter, but only a limited number of Imposters can invade any given Trial: while the others wait, they act as the the eyes and ears of their murderous teammates. Each Imposter will get a chance to invade the Trial, as their peers succeed in their sabotage… or die trying.
With the update they're also now using Easy Anti-Cheat, which has been disclosed on the Steam page as of today. Anti-cheat is rather problematic when it comes to Linux / SteamOS + Steam Deck, but in this case they do have it enabled for Linux platforms to be able to play. We were shared this message from a support ticket the developer replied to:
I've personally tested it just to be sure and it worked fine with a game being invaded on Desktop Linux (Proton 9). Nice to see, since it's a Steam Deck Verified game. Our dedicated anti-cheat page has now been updated to note this.
You can see the trailer for the new update below:

Direct Link

Direct Link
In case you also missed it, like I did previously, the developer also has an AI notice on the Steam page:
Throughout the development of our game, we may leverage AI-based tools to assist our team in content creation. Please rest assured that what you see in the game reflects the creativity and hard work of our team. Examples may include pictures and/or posters used in some of our environments.
Prefer games without any AI gen at all? Check out our recent article to make them easier to spot on Steam.