Path of Exile Sentinel was released with the attention of many players. New characters and new scenes will bring us endless fun. Among them, the game mechanism this time is also very concerned. Sentinel mechanics add another layer of extreme complexity in the form of sentry controllers. In a nutshell, a controller is a specialized passive skill tree that affects how Sentinels behave, which usually results in a larger overall bonus. As powerful as Sentinels are, they don't last long.