linuxmemes

One part would be to run a shadow client that takes the user's input and sees how much the game state diverges. There will be a certain amount of it due to network latency, but if there's some cheater using an engine mod/hack to fly around the map, this will catch that. Though something like that should be caught by a lower level check that makes sure the players are following the laws of physics in the game (like max speed, gravity applies, no teleporting).

Another one would be to see if the player follows things they shouldn't be able to see. If a player hides behind something they can shoot through but can't see through, do they somehow seem to always know they are there? Do they look around at walls and then beeline for an opponent that was hidden by those walls?

Another one would be if their movement (view angle) changes when they are close to targeting an enemy or if they consistently shoot when the enemy is centre of target, then it's a sign they are using a device that even kernel mode anti cheat won't catch to cheat (it plugs in to your input between your mouse and PC, also plugs in to somewhere that would allow it to act as a video capture device, then just watches for enemies to get close and sends movement or clicks to aim or shoot for you). Though this one is pretty difficult to catch, due to network latency. But those mouse movements might defy the laws of physics if the user was already moving. Natural movement is continuous in position and its first derivative (always, by Newton's f = ma, though sample rate complicates that), and the way we generally move is also continuous in the second derivative, but banging your mouse into your keyboard can defy that and it's even more sensitive to sample rate.

Imo these techniques should be combined with a reporting system and manual reviews. Reports would activate the extra checks for specific players (it would be pretty expensive to do it for all players), then positive matches from the extra checks would trigger a manual review and maybe a kick or temp ban, depending on how reliable the checks are.

That said, I believe there will eventually be AI-based bots where detecting them vs other skilled players will be impossible. And those will be combinable with some infrastructure that allows players to take certain amounts of control, maybe even with an RTS-like interface that could direct the bot to certain areas. Though adding an LLM and speech to text and vice versa could allow it to just respond to voice commands, both from other teammates and from the player.

I think at that point, preventing cheating in online games will be impossible and in person tournaments will probably involve using computers provided by the organizers (tbh I'm kinda surprised this isn't already the case and that some people have been caught using cheats during these kinds of tournaments).