The same applies to your own character. Merely to show you how bad this really is, the stats are like this- sporting a ranged top, bottom and helm when meleeing reduce your precision by 27%. Wearing a MAGE top, bottom and helm when meleeing reduce your accuracy by a staggering 45%. Boots and gloves don't appear to have a massive impact however.
These two points are why you should exploit the weakness of this monster. If you're combating Dark Beasts (that mage you currently ), and show a weakness to scope, and you choose to melee, well you'll notice two points. One is that you can hardly hit. Two is the magic harm actually adds up today because of your armour. (A way to get around the last part is by simply wearing Hybrid equipment, such as the Warpriest of Armadyl gear obtainable as a drop from Aviansies and other monsters in the GWD)
Oh, and you should definately get a Royal C'bow. Ammo is extremely cheap, prices only over 1M to make, and it outhits CCB. And one last thing- Use skills as often as you can. If I'm casting Fire Surge on a glacor, and that I use a magic skill, I DO NOT USE UP ANY RUNES AT ALL. Same with arrows in scope. To get slayer tasks, you would want to prevent ultimates, and focus on basics and thresholds, until you're able to utilize Guthix' Blessing to cure, or Berserk/Metamorphosis for some mad damage. I just explained almost everything there is to learn about the EOC for you. Maybe I should write a manual about it. And if you need any more help, PM me here, or in match:"Renegaderp". Always use 2H or double weaponry for slayer tasks. Go with the maximum tier weapon you've got. If you got a lv 80 ranged wep along with a lvl 80 melee weapon because your greatest tier firearms, use the weapon which the monster is weakest also (based on combat triangle). You will never want anything longer than bandos/ barrows to get slayer tasks. If you do need any lvl 80 weapons, I believe its better to find chaotic weapons and save your money on anything else. I think people should only pick the lv 90 stuff if they've got money to burn. Up to you though.
Bombardment works too if you have monsters near each other and also have spare adrenaline. 2h Ranged: precise same as above but swap Needle Strike for Dazing shot.
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