Well the best boss killer dryad must follow the hunting skills.You should maximize tactics lore and dexterity.An other trick in killing bosses is keeping ravanged impact at low level in order to use it every second.So you must use the hunting focus mod in sinister predator.You should also use the double shot and armor ignorance in ravanged impact mods.Then you will very easilly kill bosses.You should also use constitioution,especially if you plan to play in hc as well as armor lore and combat reflexes.You must also use ranged weapons lore, but dont raise it a lot because you will use sinister predator for attack sprrd and attack value.I hope I helped you!!