With a major midseason update out today, Embark Studios have given an update on their anti-cheat plans as more tools are being added to it. The game should still fully work on Linux / SteamOS platforms (like Steam Deck), as they've said multiple times before they won't be doing anything in THE FINALS to specifically block Linux.
They confirmed previously that Denuvo Anti-Cheat was in their plans, but the actual rollout of it as an additional tool has now begun which they said should be finished by the end of next week. They said "Denuvo AntiCheat turned out to be a perfect complement to our existing tools. Rollout will start with this release, and complete by the end of next week", so we assume this will be in addition to Easy Anti-Cheat that it already has. We're noting both on our anti-cheat page to be sure for now.

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Along with the anti-cheat update, THE FINALS also has a whole new free-for-all Halloween event that sounds pretty fun:
Did you hear that? That’s your cue to run!
In GHOUL RUSH, everyone starts off as a Survivor in this brand new, limited-time, Free-For-All mode. Get eliminated even once, and you’ll be doomed to spend the rest of the round as a Ghoul, hunting down the remaining unturned Contestants! Each match lasts for three intense rounds, so you'll have time to switch your tactics and seek revenge!
Earn cash as a Survivor by eliminating Ghouls and other survivors, by staying alive for as long as you can, or by making it to the end of the round as the last surviving Contestant! Once you’re a Ghoul, earn cash by eliminating Survivors.
Enter the foggy and frightening ALFA-ACTA P.E.A.C.E. Center for this event and take a fixed loadout with you, depending on your choice of Heavy or Medium Build. Once you’re a Ghoul, you’ll need to either rely on your Sledgehammer or your trusty Dagger and, of course, what’s left of your wits!
Can you survive the Ghoul Rush?
In regards to their next game, ARC Raiders, which releases on October 30th — Embark and their press teams have not replied to multiple emails from GamingOnLinux to confirm if the release will have the anti-cheat enabled for Linux. We go with the thought that just because one game from them works, it does not mean the next will (since anti-cheat is such a problem for Linux gamers). Also, just because previous playtests for ARC Raiders worked, doesn't necessarily mean the release will when everything is online. We've emailed again today to see if they finally want to talk.
Did you hear that? That’s your cue to run!Could be an unintended honest statement about the Denuvo roll-out.