Garry's Mod anti-cheats that are no longer maintained

Search for a Garry's Mod anti-cheat and the old forum threads still recommend !cake Anti-Cheat, LeyAC, QAC, gAC and SimpLAC. None of them is maintained in 2026. Each one stopped being updated years ago, and most were client-side checks that newer cheats were built to get past.

This page is written by Mizan, which makes a Garry's Mod anti-cheat, so read it with that in mind. Every fact here comes from each project's own repository, listing or author, read on 5 November 2026 and linked at the end. If something is wrong, email contact@mizan.ac and we will correct it.

!cake Anti-Cheat (CAC)

!cake Anti-Cheat was a paid, heavily obfuscated client-side anti-cheat on GmodStore, and for a few years the one most servers ran. Its detection code was never published; the only public repository holds its admin interfaces and was last changed in January 2016. GmodStore disabled the listing, and a 2019 thread on GmodStore quotes the reason it gave: "Inability to detect more recent cheats, lack of updates." The listing now needs a sign-in to view.

LeyAC's author, writing about CAC, says it depended on a central database of cheats kept by its developer, and "once the developer stopped updating said DB, it died out as well".

LeyAC

LeyAC was Leystryku's client-side anti-cheat from about 2012 to 2014. Its code is now on GitHub, described as an "Abandoned clientside AntiCheat from 20122014", last committed in May 2021. Its README says: "There is sadly no support. This is legacy software." It worked by learning what a legitimate player's game looked like and flagging what didn't match; its author notes that building that list for every update, server and addon combination is "a NP-hard problem".

Leystryku now sells LSAC, a server-side anti-cheat, and SwiftAC, a scanner for Lua cheats.

QAC (Quack Anti-Cheat)

QAC is a free, GPL-2.0 client-side anti-cheat whose last commit was in October 2015. According to the LeyAC README, it "only focused on validation of the filenames of code which was run", so "Renaming Cheats to have legit names was enough to fool said system." Its own readme admitted that "there is ways to get around that is actually impossible for me to fix".

gAC (GlorifiedAnticheat)

gAC is a client-side anti-cheat that its own repository calls "The leading Garry's Mod anticheat from 2018 to 2020". It checks the player's Lua environment, console variables, rendering and debug library, with 31 detection codes.

It was private until its code leaked. On 17 March 2020 its author wrote in the README: "After around two years, we've had a leak where I believe that me simply releasing g-AC as public will be a better alternative than attempting to recover via new detections." The same note said it "won't be supported or updated".

gAC has been free on GitHub since. Its last release, 2.1.6, came out in August 2020, and its last commit, in August 2023, removed its Discord link. The README now opens with: "PLEASE STOP CONTACTING ME ABOUT G-AC, I WILL NOT HELP YOU".

SimpLAC

SimpLAC was Leystryku's server-side anti-cheat on GmodStore, with "behavioural (for example too high FOV changes) and analytical (for example too high k/d ratio) checks". Its listing is now titled "[deprecated] SimpLAC". The LSAC listing calls SimpLAC "the spiritual predecessor" and asks you to remove it before installing LSAC.

KAC

KAC (Kyle Anti-Cheat/Anti-Crash) is a free script against server crashers and cheaters, built alongside Hazard's addons. Its README says "Development has stopped with the shutdown of Hazard", and of its aimbot detection: "controller emulators cause false positives, wont fix". Its last commit was in August 2022.

Why they stopped working

Most of these ran their checks on the player's own computer. That catches a known Lua cheat as it loads, but the cheater controls that computer and can read the checks, and today's paid cheats are compiled DLLs that run outside the game's Lua entirely. A client-side anti-cheat has to keep up with every cheat by hand, and when its author stops, it stops.

The anti-cheats still being built for Garry's Mod judge what players do on the server instead, or add server security around a smaller client-side check. The best Garry's Mod anti-cheats in 2026 compares the six still sold or maintained: Mizan, Chronon Labs, LSAC, SwiftAC, Nova Defender and Trinity.

Sources

All read on 5 November 2026.

• !cake Anti-Cheat: cac-administration on GitHub and the 2019 GmodStore thread.
• LeyAC: legacyLeyAC on GitHub.
• QAC: Quack-Anti-Cheat on GitHub.
• gAC: GlorifiedAnticheat on GitHub, and the 17 March 2020 README change about the leak.
• SimpLAC: its GmodStore discussion page and the LSAC listing.
• KAC: KAC on GitHub.