Simply kite "Storm Giant" (his spawn is relatively close to New Agamand) into new Agamand. As soon as you get near the guards they will aggro on him and start to attack. The funny thing is they die within about 7-8 hits from him. Eventually after killing the first set of guards he will go on to kill all other guards and players in surronding range. Pretty well everyone dies.
Note: Guards are close enough together to usually keep him from evading and running back. If none are seen, pull him to an area with more guards.