Do not use This plugin with Spigot 1.8.1 and Above i have used it with spigot-1.8.7-20150608a.jar and Its Very Bad . [Server thread/ERROR]: Could not pass event BlockBreakEvent to AntiCheat v2.0 org.bukkit.event.EventException It will cause your server to crash multiple times a day . the new spigot Build cannot handle BlockBreakEvent. Just a notice for you Guys out there to keep your servers running smooth!
Well AntiCheat is outdated and abandoned for more than a year already, you should be using something like nocheatplus instead.