The anti-cheat software associated with League of Legends on Windows is Riot Vanguard.
Vanguard is Riot Games’ proprietary anti-cheat platform, originally introduced for Valorant and later added to League of Legends. It combines a client component with a Windows kernel-mode driver, allowing Riot to detect certain cheats that operate at a deep system level.
The date in the question is easy to misremember: League of Legends began requiring Vanguard in 2024, not 2023. Nevertheless, Vanguard is the single canonical answer to the software question. PunkBuster, BattlEye, and Easy Anti-Cheat are third-party anti-cheat systems used by other games and are not League’s current solution.
Vanguard’s rollout prompted debate about privacy, system access, compatibility, and its startup behavior. Riot has defended it as a way to prevent scripting, bots, and other forms of cheating in a competitive online game. Its use in League followed several years of operation in Valorant.