Priest in Peril, Creature of Fenkenstrain, The Grand Tree, Zogre Flesh Eaters, Lost Tribe, The. You must also have one of the following: Regicide started, or The Fremennik Trials done.
Level 40 slayer (and you must have done the little Mogre mini-quest to have access to fighting the mogres). Also, you must have the ability to kill monsters that are up to level 88.
Need some armours and food.
A Bonesack or a Ram skull helm
5,000 Prayer experience
Tips, tricks & notes:
Your in-game quest journal shows a list of bones you still need to get.
If you enter the Lumbridge caves through the basement you won't need a spiny or slayer helmet. Just go south to the frogs.
To make brutal arrows, you are required to fletch achey shafts. Each shaft requires 4 feathers to be flighted. Together with a hammer, you attach nails to the shafts. Each bar produces 15 nails.
You can change or retrieve your Bonesack or Ram Skull Helmet from the Odd Old Man whenever you want.
Bonesack: All defence stats +4, no other stats, wields in cape slot (it is only a cape that looks like the bonesack that guy is carrying, it does nothing else).
Ram Skull Helmet: Defence stats: Stab +19, Slash +21, Crush +16, Range +19 (and -2 to range attack stat). Wields in helmet slot
The required bones are NOT the normal bones they drop, but a special, non-bury-able bone that you can only get after starting the quest. This also means that you can't acquire any of these bones before starting the quest, even for the monsters with unique bones (such as Monkey Bones or Bat Bones).