You need ProtocolLib (3.6.x for 1.8 version) http://dev.bukkit.org/bukkit-plugins/protocollib/
You MUST use ProtocolLib build #89 and above for Bukkit/Spigot version 1.8.3
AntiAura is a bukkit plugin that allows you to test if a player has kill aura. It basically sends a packet to the player that spawns a configurable number of fake players for a configurable amount of time. The message is sent to administrator with the result (how many test players were attacked).
Commands:
/auracheck <player>
/auracheck reload
alias: /ac <player>
permission: auracheck.check
Configuration:
ticksToKill: 10 #how much time in ticks to give player to kill the fake players (20 tickets in every second) amountOfFakePlayers: 4 #how many fake players should spawn I recommend 5-7 invisibility: true #should fake players be invisible (some kill aura hacks may ignore them)
SourceCode: http://github.com/maciekmm/antiaura