As someone who has been in the graphics card driver side of things for almost 3 years now, anti-cheat has been the bane of my existence. Some anti-cheat has been strong enough that is has actively stopped me from fixing games, doubly so when we can't get into contact with the game developers. I would not be surprised if in the future some games might just never run on one gpu due to a mix of anti-cheat, legal, and driver signing troubles.
While I have a massive disdain for anti-cheat enough that I've built hacks just so I can fix the games my employer pays me to fix, I'm not going to encourage developers to drop them if they truly think it's needed. But please, contact gpu manufactures and provide them the tools or builds needed to fix and debug your game.
Cheating in online gaming is such a blight on the industry. Such a waste of time & money for every legitimate participant in the market, except for the groups making and profiting of the cheats of course.
I still like my idea for a third-party reputation service that has consequences for not just one game but every multiplayer game participating in the program: https://news.ycombinator.com/item?id=28634784
I really do think it would make cheating non-existent, and allow developers to focus on building cool games instead of building invasive & ineffective rootkits we have to install just to play games online fairly.
At first I was optimistic that AI would greatly alleviate the issue here, but no dice.
As someone who was super competitive about the games they played (reformed, no longer play), I can tell you online cheating is completely out of hand.
There are cheats nowadays that don't even require software to be on your computer. You just put up a camera on your screen and an AI bot helps you by manipulating your controller (e.g., aim) - it really is a cat and mouse game and I don't think the issue in general will be resolved anytime soon.
I know there is an entire industry built around gaming and custom PCs so this is a pipe dream, but I'd love it if instead of all the time and effort that goes into supporting these rigs, the business models for consoles were optimized such that consoles could be top of the line rigs with very strict upgrade paths. This is really the only way I can see us actually putting a dent into this problem
You can now upgrade storage, perhepharals, monitor and usually have at least a generation of backwards compatability the lines are blurring.
I can also get more then twice as many headshots if I plug in a mouse inplace of a controller when dose that become cheating for people wanting to play from the couch?
Not sure if any vendor verified hardware program can avoid lockin due to economics, but it would certainly be nice.
> There are cheats nowadays that don't even require software to be on your computer. You just put up a camera on your screen and an AI bot helps you by manipulating your controller (e.g., aim)
I haven't paid much attention to that scene in a few years, but I'd be a bit surprised if things had advanced this far already. Do you have any names/links I might search about this?
> I still like my idea for a third-party reputation service that has consequences for not just one game but every multiplayer game participating in the program: https://news.ycombinator.com/item?id=28634784
So, essentially China's Social Credit Score, just for gaming... a bad idea IMHO, a really bad one.
For one, that centralized reputation service that actually has data linked back to government-issued credentials (ID cards, passports, ...) must be ridiculously secured, because it will be among the juiciest targets on the planet - be it trolls or deranged stalkers of either gender (although most tend to be male [3]), people are willing to go to ridiculous lengths to abuse fellow gamers, especially (large) streamers. Ordering pizza, SWATting, or even cases of rape and murder [1][2], all of that has happened. Give 4chan enough incentive and they will crack open anything. Or they'll just outright infiltrate the company, someone has to run it after all, and whoever has admin access, no matter the audits and internal controls, will find a way to exfiltrate stuff.
And even assuming the reputation service doesn't get hacked, the participant games are another target - this time, not for the data that's held by the reputation service, but for reporting "cheating" by the target person. Either technical bugs or infiltrating the customer service, both can yield results - game companies largely crap on code quality, even the biggest ones (remember Rockstar's GTA JSON bug lol), and customer service jobs are low paid and have high attrition, easy targets for infiltrators.
And then gamers themselves are also valid targets. Manage to get a piece of malware onto a streamer's computer that gets detected as a cheat, boom. And that's easy to do, RCE vulnerabilities crop up every now and then for major games (Minecraft for example had BleedingPipe and log4j, GTA had one in 2024 and in 2023).
Making some assumptions here but I suspect most game developers outsource their anti cheat to a 3rd party and that is what you are running into. Some of the 3rd party anti cheat rootkit computers. Some are okay and some are just terrible.
You're correct, most companies don't make their own anti-cheat. We have categorized the different anti-cheats and have ways around them where needed. But whether or not the game devs or some 3rd party makes the anti-cheats it still leads to the same problems, I'm blocked from fixing their games on our hardware. I can't/won't share to many details about or internal process.
1) We're dependent on external tools for capturing and debugging shaders, most of which are detected as debuggers by anti-cheat and will kill the process before we even have a chance of reproducing the issue.
2) The other thing is driver signing, our solution use to be just production sign drivers and test with those, but Microsoft didn't like that we could sign as many drivers/dll as we wanted every single day. So they limited us to X per day and told us to use Test Signing which anti-cheat still detects and blocks. We have other methods too, but they're all slowly being detected by anti-cheats.
Guess, but GPU drivers have been known to change shaders being sent to the GPU for certain games, to fix things and increase performance, it's possible this could be detected as some kind of cheating by the anti-cheat.
Good guess, but most games don't actually look for that. The closest I've seen is them saving off the final rendered image and checking for wrong information. I think Vindictus was one that did that (learned about that outside the job so I have no issues sharing that.) I believe they mainly used it to detect cosmetic mods that might cut into their profits.
We only really replace shaders to fix issues that the game devs won't fix, and only then when the game isn't updated very often since it has a high chance of breaking our patches. On top of that I don't believe there is a good way to pull the information back from the driver in a reliable way, so it would be very hard to rely on any information that comes back from the driver.
> I'm not going to encourage developers to drop them if they truly think it's needed.
When I've only got an hour or two to game and my gaming friends can only get everyone together once a week, it's crushing to have a good game ruined by cheaters.
Hopefully gamedevs can work with people like you to fix bugs. However, leaving anti-cheat out of multiplayer games is a complete non-starter in today's environment. Even if anti-cheat only slows the cheat devs down and turns into a game of whack-a-mole with cheats, it's still preferable to having every game get crushed by cheaters every time you play.
Don't get me wrong I understand the sentiment there. I'm sadly locked out of most of those games from the get go being on linux though. Most of the games that give me trouble aren't online games to begin with. Most online games we do have good contact with the developers since they're typically actively working on the game.
Don’t really play multiplayer games anymore, but back when I did a lot there was a “vote kick”/“vote ban” feature that people used to get rid of the cheaters instantly sniping everyone from across the map, it wasn’t like they were very subtle.
Does that simpler social approach not work anymore?
As of about a year ago, Team Fortress 2 bots were so pervasive that they would often teamu p to use the "vote kick" functionality to kick non-bot players from public games.
This started about 5 years ago and continues today. They aimbot, spam both voice and textchat, dodge bullets, can fly, and hijack any vote to ensure their continued survival. If you can't get an invite to a private lobby you may as well play a different game. Either one that has anticheat or something singleplayer. If there was a silver bullet that made online play nice and respected your computer, someone would have shot it by now.
If you hadn't heard, there was a recent clean up and botting has become basically non existent in TF2 now. It went from completely unplayable to being the experience everyone once had. Don't know how long it will last but you can hop on and enjoy it while it lasts.
Ok that’s pretty hilarious, but what’s the point, is this just like playing battlebots for TF2 bot authors? (But if it was couldn’t they set up a purpose-built server for that?)
It’s not that they want a human-free environment or something. It’s all about causing grief. So it’d be targeted at a chosen victim probably to annoy the fuck out of them. Cheater has a button that can kick you out.
It hasn't worked for a looooooong time, you'd have 4chan and its offshoots running around coordinating offsite to yeet random players. And that was in an era where people had to pay for games and risked global bans (UT2k4 had that) on their license #, nowadays in the f2p game scene that has zero cost attached it's become all but pointless.
Some games this is still applicable. But as of a few years ago, there's been a LOT of multiplayer shooters coming out with a battle royale style of genre, where you load into a 30-40 minute match with a single life and are booted when you die. You don't have access to a list of players at any point or votekick/voteban mechanics, at best there'll be a report button on the death screen if you thought something was fishy. So you really have no way of knowing in these games at what point the match will be ruined, someone can toggle cheats on 20-30 minutes in and you won't know until you die to them nor have any way to communicate that to the other players still ingame.
When they first added this feature to Overwatch, one of the best sniper players in the world got banned because people thought he had an auto-aim cheat. Turns out he was just really really good.
Question for people that build hacks: given how robust this open-source anti-cheat is, does building the cheat give more reward than playing the game? It seems like it would take a ton of hours to be effective..
I've built hacks to undermine recurring payment structures in games. It has very little to do with cheating, and everything to do with fighting a corporate trend that I would like to see abolished in games.
Gaming companies care far more about these kind of hacks, but frequently lump them into the "cheating" category for better optics.
There is huge money in making cheats and this one seems to operate in userspace only. Most cheats and anti-cheats these days are running in lower rings (kernel or device driver)
I believe there is also hardware cheats but I'm not sure how common those are. EDIT: See "DMA cheats" or "DMA cards"
Recent keyboard cheats (ie minimising the learning curve in seamlessly changing direction when strafing) are nothing, and not really what anyone means by hardware cheats.
What is meant are PCIe hardware devices that can use DMA to read and write data without being detected by software processes at all.
They've been around for quite a while (5+ years?), but I doubt they'll ever get mainstream adoption.
If these things get mainstream adoption their PCI IDs just get blacklisted (they do need to register with the system first), or IOMMU configuration will be yet another thing to fingerprint. IIRC, the host CPU has to allow the "evil" PCIe device access to memory, or is that just something that Thunderbolt chips implemented after malware authors used this for insta-unlocks?
So what, as soon as these things become mainstream cheating targets, anticheat vendors will force (or "strongly suggest") to hardware manufacturers that every piece of hardware has to have some sort of uncloneable TPM-style module to verify authenticity.
They already are in many games where good undetectable cheats are 100$ monthly subscriptions. Anticheat vendors don't have enough pull to pull that off, Microsoft maybe could but most of their effort goes into protections against advesaries other than the computers owner.
In this instance one of the things they do is ignore keypresses at certain times
> Razer and Wooting’s SOCD features both let players automate switching strafe directions without having to learn the skill. Normally, to switch strafe directions in a first-person shooter, you have to fully release one key before pressing the other. If both are pressed, they cancel each other, and you stand there for a moment until you release one of the keys. SOCD means you don’t need to release a key and you can rapidly tap the A or D key to counter-strafe with little to no effort. [1]
Huh. That seems like such a weird, minor advantage to attempt to ban. I expect most anyone playing FPS would pick this up naturally.
Also seems impossible to ban given the ubiquity of custom keyboards running something like QMK. Those run user code and could send a fake vendor id to the host.
> Huh. That seems like such a weird, minor advantage to attempt to ban. I expect most anyone playing FPS would pick this up naturally.
With a regular keyboard its very possible for a person to not release one key before pressing the other in a tense situation when they have less than 1 second to react. For example even a professional baseball player making millions of dollars can drop a routine fly ball.
It’s actually less sophisticated - it’s merely the choice of what key input is reported when two keys are physically in the down position, simultaneously.
“Report last key that was activated” means that rapidly switching/alternating between, say, A and D to switch movement directions is a matter of just pressing the next key instead of coordinating the lifting of the other key.
AFAIK this has existed as an autohotkey script for a long time, but it’s so simple a legitimate hardware implementation detail can be another vector, and wouldn’t fit in the “unauthorized software” definition of cheating so needed a separate callout.
Essentially the keyboards have software that will allow the user to override keypresses at inhuman speeds. This allows users to switch left/right direction extremely fast, which is very relevant in CS2 due to peeking mechanics.
Specifically, if I'm holding A (moving right) then I press D (move left), in most games in I would stop since I now have both keys down. These keyboards automatically raise the A key even if you're still holding it, allowing an immediate swap of momentum.
Not really, and valve has also banned these at the macro level.
They just allow you to set them up such that when you start strafing (ie moving) in an opposite direction by pushing an opposing key (ie you're holding down "move right" -> "d", but now start holding down "move left" -> "a") that there is no overlap between the "d" and "a" being held down, as some games (CS) punish having both down at the same time. Valves idea is that minimising the time gap as you switch directions, while never having the two keys overlap as pressed, is an important learned skill that novices should not be able to do as cleanly as pros, and have said that keyboards that support this seamless transition will be banned.
Go to aliexpress. Google cheat cards. They've proliferated pretty heavily in the last couple years.
My buddy and I were actually just discussing ring 0 anti cheat circumvention and we started researching these units. Our guess is that the hardware slightly changes every iteration with updated firmware to circumvent general heuristics like HWID.
Part of me really wants to do this, put a time bomb circuit that fries the PC after x hours of use, and leak them into the supply chain. Not going to do it, too much work, but cheaters ruined sooo many hours of my life.
I wonder if there are software dev counter-parts that would build cheats just to soft-brick cheaters PCs...
I don’t know what to say. Cool project, but I would be mortified to admit to using this. Cheating in a competitive game is just griefing with self-delusion and extra steps.
You’re also going to never be able to have a professional relationship with an athlete or gamer ever again. People who have dumped thousands of hours practicing to get good at something, and you’re proud of cheating them and people like them?
Enjoy your s3 emerald skins. I’ve reported your accounts to embark.
> People who have dumped thousands of hours practicing to get good at something, and you’re proud of cheating them and people like them?
Just as a hypothetical situation - what if one had built a similar tool on their own, or used this as a foundation but trained a new model? Does it count, or are we denying this as a personal growth and limiting it strictly to playing exactly by the book?
Alternatively... What if someone has a physical condition that limits their manual dexterity? Is it different from having a physical condition that limits their eyesight and have to wear glasses?
I'm trying to draw a line. Or challenge the status quo where the existing line is drawn.
What if someone did not have the physical strength to become a champion cyclist/baseball player, but found a medicinal way to overcome their limitations and achieve peak performance in their field? We've already come to a decisive conclusion on this; steroids are banned in most sporting competitions. Just as cheats are in online games. Just because someone does not have the pure physical ability to compete at the highest level does not give them leeway to cheat.
> We've already come to a decisive conclusion on this
Have we, really?
In the professional sports there's WADA and similar agencies, that, obviously, have to push this idea really hard (and make everyone believe that everyone else thinks so, because this is how you do it in modern times). But that's because that's what's literally keeping them afloat. But they're already struggling, trying to figure out what to do those gender-to-chemicals mismatches. And as sciences and societies evolve, I suspect it's only going to get more interesting, and I have this hunch that this status quo has cracks in its foundation and will likely shatter in the future.
They also have to make sure that athletes are safe enough and don't just wreck themselves - which makes things a quite bit different. Unless we count risks of issues in some people with predisposition to toxicity, that is associated with cheat use /s (no love for those folks).
But back to the "have we" question - do people actually care about all this stuff in non-professional sports when played recreationally? (Just like video games.) I really doubt so. People just try to balance around it, fixing the matchmaking rather than players.
But - you certainly have a point - I would suggest to exclude professional scene entirely and narrow the scope strictly to recreational gaming. Pro sports and e-sports are more controversial.
It's hard for me to think of many equivalents of video game cheats to professional sports in the sense that most "cheats" for professional sports that I can think of don't "play" the sport for you. A normal everyday joe can't just wake up and start taking steroids one day and place anywhere near the top in olympic or power lifting (or even anywhere near the middle class of amateur, clean competitors who have been training for a few years). Nor can he do blood doping and hope to compete against world class cyclists. Or in any way go up against and win bouts with masters of various martial arts. In one way or another those methods of cheating still require incredible amounts of effort, training, etc. to utilize. But a video game cheats like auto aim, wall hacks, radar, or the more blatant ones like infinite health, speed hacks and the like let someone with no skill or preparation just jump in and casually outcompete even the best of the best in a way that allows for little to no opportunities to outplay them. I'd say it's less like using steroids and more like showing up to a deadlift competition with an industrial crane.
To get to the point, I think this is why less people seem to care in non professional sports if some random guy who is on performance enhancers shows up to your amateur soccer match or pick up basketball game. The gap at the amateur level between a clean amateur and cheating amateur is not so large and certainly overcomable if the clean amateur has more training.
> do people actually care about all this stuff in non-professional sports when played recreationally? (Just like video games.)
People absolutely care, because a cheater in a lobby will ruin the experience for a dozen or more people and ultimately waste their time, taking it away from their lives.
The cheater is doing it willingly and knowingly and with a full intent to cause harm - take away someone’s time which is really the only thing we have. Cheaters shiho absolutely be punished beyond just video games, not sure how exactly though (I wouldn’t trust state nor mob with that task for sure)
Video game cheats are nothing like sports cheats / steroids
A non-roided pro can still sometimes somehow beat a roided pro.
With videogames there is zero chance you can actually beat a cheater. Maybe you can score a lucky point / frag against him/her once in 100 instances, but actually beat him?
Imagine idk Mike Tyson in his prime comes up against an underdog and the underdog can teleport or has a perfect reaction time of a standard auto-aim cheat?
Not him, but why? Cheaters in multiplayer games seek a gain for themselves at the expense of everyone else playing. They provide no benefit to a community and it's not something anyone should be even remotely proud of, even if they put a significant amount of intellectual effort into doing so.
A few years ago, I used to play EFT with friends after work and putting my kids to bed quite frequently. For a group of friends living quite far apart it was one of our favorite gaming experiences as a group. But our feeling on it soured as the game was slowly but surely taken over by large amounts of cheaters in every single match we played. The developers weren't able to deal with it at all and eventually we all quit playing. There's nothing that takes the wind of your sails in gaming like sitting down to unwind for the hour or two a week of free time with your friends and just being completely unable to enjoy that time because a significant portion of the lobby is made up of selfish cheaters. I can remain friends with someone who cheats in a multiplayer game but I never play with them after finding out they did so. I don't hesitate to report accounts. There's no benefit to you as a player keeping them around unless you're somehow making money off cheat sales.
My disdain primarily comes from going out of your way to snitch on someone, regardless of why.
But in general I'm not upset with cheaters anyway. People are always going to push boundaries. It's a fact of life.
I also believe that most cheats, at least the more invasive ones, are only possible because the game was poorly designed, without cheating in mind. Instead most game companies seem to just slap a commercial anticheat product on top and hope for the best.
I see, thanks for clarifying. I guess my frustration with that viewpoint comes from a personal bias- I can't share any sympathy for reports of that nature after seeing many of my friends and my own hours "wasted" when budgeted free time that could have been lighthearted and relaxing turns into frustration, venting, anger etc. after getting repeatedly shut down by blatant cheaters (though one could say games are wasted time in and of themselves). That I paid for the game to play with friends and none of them are willing to play it anymore because of how ineffectual the developers were at dealing with the problem compounds that frustration.
I do agree that developers should put more effort into thinking about proper design and anticheat protections. But it's also a huge ask for smaller or more inexperienced studios when they have to waste time dealing with bad actors that could have been better spent on game development, and an excuse for antisocial cheaters to keep behaving poorly. People want to assume the best out of each other. In an ideal world, people who can't keep themselves from making their hobby that of making others miserable for pleasure would be the ones being punished instead of laying the blame on those naive enough to assume that everyone is good natured and cooperative.
I agree, it's not, and people should be more careful. But at the same time it's just strange to me to see someone actually trying to clean up an online community and make it more ideal labeled as "pathetic" and a "snitch," as if a cheater's right to waste other people's time and pleasure is more important and people should just accept someone bragging about acting poorly in a social context. I don't think that's very productive behavior.
The thing is they're not really going to accomplish anything. Okay the accounts were reported. Great. Good chance no one is ever going to look at it and nothing will happen. The only thing accomplished here was the original poster trying to gain brownie points for doing a good boy thing (and then bragging about it).
Btw, they definitely did not find my steam account or actually report me. Even if they did, it’s literally a free shooter. Id be on another account within minutes. Yes I’m aware of how to get around HWID/IP bans…
Glad to see that my comment caused quite the shit storm though.
> does building the cheat give more reward than playing the game?
Absolutely! At least for the kind of people who like cracking games. Think of it as a puzzle game.
Being able to play the game as a cheater is like getting the final weapon in a game where it requires completing the most challenging part. You have fun for a bit, destroying everything in your path, that's your reward, but you quickly lose interest as you have nothing interesting left to do.
Just like any software, game cheats are build once, sell as many times as you can. If a game is popular, this can be a very lucrative business. The fact that game developers will play the cat and mouse game with you to block you out only adds to this fact, as so long as you can keep up, you can get repeat customers.
Now I want to read an article about the economics of selling game hacks. I just assumed they weren't really worth the investment to build since the number of people that want to cheat seems low.
After typing that I realize this is like coming to understand just how many people are on steroids to get a physique they want. It's like nah no one takes steroids except EVERY HUGE PERSON you've ever seen, barring the extremely rare genetic outliers.
Would recommend this podcast from Darknet Diaries. [1] Not quite an article, but there is a transcript if you'd prefer to read. Includes interview with the people actually selling these hacks, and it is fascinating
yes- I have been out of the "game" for a while, but, the economics are strong. Used to sell bots that could automate tasks to get gold in various games (WoW and Runescape as examples) and we had customers that would buy 100s of licenses monthly and had factories that they'd use to farm and then sell the gold on eBay, etc.
I don't get how pwning noobs is gratifying at all. It's just griefing and for a normal sane person there's no fun in seeing other people suffer. It's like wrestling with toddlers.
Proper "cheating" is not about wreaking havoc. Although there are plenty of weird people who do weird things - but cheats are not a problem, they just enable those weirdos to do weird things.
It's just automation, all about offloading work to a machine - a principle that the whole human civilization is built upon. And developing an aid that actually helps you to improve is - surely - a personally gratifying experience. If someone has difficulties doing something the "intended" way, but can think of and implement an alternative approach to achieve the same effect - that's just humans being humans, it's as fair as life can be.
I wonder if a statistics-based cheating detection system could work in more of the esports style games? Chess.com seems to have a pretty good method to detect cheaters based on analysis of post-game data: https://www.chess.com/article/view/chess-com-fair-play-and-c...
Even in something like an FPS, if player movements or action patterns could be compared to normal patterns, it would be incredibly obvious who is cheating regardless of HOW the player managed to cheat.
Even something as elaborate as a full AI-powered robot that physically hit the keys could be detected when it made a move that was not within the patterns of human players.
Of course, the cat and mouse game then becomes more about the cheat algorithms learning to act more human to avoid detection, but they have a long way to go. Plus, each time they have to adjust and become more human, the less and less of an advantage the cheater has!
I'm not actually good enough at anything to be tempted to cheat, even if I were persuaded to become ethically OK with it. But if I were, I think that's where I'd start. Oh, some game is blocking a specific model? A recompile of the firmware says look at me, I'm a Microsoft Ergonomic Keyboard!
Nobody wants that running on their computer though.
Maybe it's time to just give up on PC gaming and use dedicated game consoles instead, which are locked down by design? The only real alternative seems to be running a cryptographically-verified known-good OS signed by one of the big three OS companies, which is also locked down enough such that cheating becomes impossible, or installing what is essentially kernel-level malware, just to play the latest games.
Does it matter when userspace software can already read all your files and access memory of processes run by your user? This kernel access boogeyman is practically meaningless.
I don't think this is possible on Windows without administrator. It certainly shouldn't be, if it is.
But anyway, the fact that any userspace software can read all your personal files without any user confirmation as soon as you double-click on it is not a good thing, and as I said, all desktop operating systems are attempting to address this problem in some way, including Windows. I imagine the normalization of rootkit-style anticheat has become a pain point for the security team at Microsoft.
Sandboxing on desktop isn't there yet, but on macOS and Linux it's possible to sandbox games such that they only have network access. If most games start requiring administrator/root access for anticheat purposes, sandboxing them at all becomes a non-starter.
I don't play that game but their anticheat is best in class. All modern anticheat that pretends to be effective has a kernel driver anyway.
But I was asking why people believe that they're safe from userspace software they install as that can read all the files and memory of processes of your user anyway.
Games or esports? Riot’s Valorant used a kernel level anti-cheat that needs to be enabled at boot.
It’s super problematic from a security perspective.
That being said, I’ve played competitive FPS games my entire life, and valorant is the only game I’ve never ran into a cheater in. So it works, and I’ll say, it should be a hard requirement going forward for the anti-cheat to be a core part of the game architecture. A game getting popular enough to attract cheat developers to make an sdk for a game isn’t “suffering from success.” It’s a death sentence for the game. There are popular streamers and YouTube content creators out there that go through extreme lengths to avoid cheaters, but in the end they always just stop playing the games.
Pretty much all anticheat is kernel level because that's where hacks are now, it was not a new thing when vanguard came out either, it had been like this for years already.
Not that it matters that much for data privacy if you game on the same user anyway as userspace anticheat can access all your users data.
I have 1000+ hrs in CS and I'm glad VAC exists. I've seen tons of hackers get vac banned, thank goodness. I'm confused...like I know VAC isn't perfect but how does it ruin TF2 specifically?
TF2 is overrun by bots farming hats. CS has always been completely infested at higher ranks like global elite. In both cases VAC is practically useless against any non-userspace hack.
It's not right now, there was a huge banwave and it's been bot free for a couple of months now. If you have any nostalgia for TF2, now is the time to indulge.
IIRC Overwatch's anti-cheat is also entirely user-space and server-side, and I encounter relativly few cheaters in Master to GM lobbies. Not to say there aren't any (there most certainly are), but there are so few that are noticable that it honestly is negligible IMO.
This is fundamentally the wrong way to do anti-cheat. Anything you do on the client will fundamentally always be bypassable, and it tends to always have at least some negative side effects. Proper anti-cheat needs to happen on the server.
Doesn't work. Say, a shooter has support for surround/immersive audio - the client has to know where an approaching enemy is so that it can appropriately render footstep sounds or shadows. That in turn can be used by cheat aids to warn about someone sneaking up on you.
I don't think the situation is so clear-cut to be able to make categorical statements like that: server-side cheat prevention is also bypassable, and depending on how it is implemented, also has the potential for negative side effects. No matter what approach the developer takes, they're going to be making a trade-off of efficacy, player convenience, and developer effort, and that trade-off is going to be influenced by a lot of different things, such that client-side cheat prevention (or, likely, a mix of client-side and server-side measures) will be the most reasonable option in at least some circumstances.
It's not possible because the client's representation of the information from the server is an important part of the "gameplay". In typical network applications (that are not video games) the client's interpretation/representation of what the server is sending is entirely for the usability of the application. Maybe the client displays an array as text list, a series of cards, different tabs, etc. It's just about what makes sense to a particular client/user and what makes their life easier. It's not "unfair" for me to have an email client that highlights unread emails differently than you.
In a video game, different interpretations will give different people different, unfair, advantages. There is an "agreed upon" representation from the developer of the game that's supposed to be "fair" for everyone. Displaying audible ques as visual ques is a "cheat". Highlighting a piece of information or an object is a "cheat". Auto-interpreting information you're supposed to parse yourself is a "cheat". Not every cheat is God-Mode breaking-the-physics-of-the-game cheat. Plenty of cheats are just about having a slight edge over others.
For example, your game has a minimap. Part of the "gameplay" is that you scan the minimap every X seconds to check if something is approaching. It's a situational awareness skill that some will be better at than others. A flashing red map when something approaches would give you an edge. Or the server is sending spacial audio information about where a sound is coming from. It's an auditory skill that you develop and some will be better at it than others. An arrow on the screen pointing to where the audio is coming from would defeat that part of the game. Being able to see a moving shadow in the distance, or when to break/turn in a racing game, or an odds-calculator/card-counter in a cards game, a parry/counter attack indicator in a fighting game, etc are all "skills" that you are expected to develop to become "good" at this game. They are what make these games fun/rewarding for people. Having tools to help you with these tasks would be considered "cheats" in these games.
At the end of the day, there are "cheats" that no software can catch. Having a friend sit next to you who just watches the minimap, or who calculates stuff for you, or watch a different part of the screen for you are all "cheats" that no software can catch.
Obviously there is some stuff to be done to limit the "exploit-ability" of the information. Don't have the server send information that the client doesn't need like the location of all players all the time. Have the server reject invalid moves, like a player flying when there is no flying mechanics/ability for that player. But at the end of the day, the minimal amount of information needed to play the game can be exploited by someone if they find a different way to represent it to themselves that gives them an unfair advantage.
While I have a massive disdain for anti-cheat enough that I've built hacks just so I can fix the games my employer pays me to fix, I'm not going to encourage developers to drop them if they truly think it's needed. But please, contact gpu manufactures and provide them the tools or builds needed to fix and debug your game.