for Lvl 60 equip slow time, energy homers and whatever u want. Every cooltime finishes for slow time, use it and keep using energy homers as well. I used rail gun to shot the boss when it summons slaves because it can kill slaves and shot the boss at once. (Big laser is good as well).
 "CycloManiacs"){kind=icon}
 "UPGRADE COMPLETE!"){kind=icon}
 "Heavy Weapons"){kind=icon}