First, you must craft an unpowered orb from molten glass. This orb must then be taken to one of the eastern obelisks all around Gielinor and the change eastern ---- orb spell used on it. The eastern orb can then be used with a battlestaff to make an eastern battlestaff.
Eastern battletaffs require a magic and attack level of 65 to wield. They provide an unlimited amount of a certain type of eastern rune. They also allow the player to autocast any eastern spell they have the magic level and runes to cast. An eastern battlestaff can be wielded to gain attack, strength, defence, magic or magic/defence XP like any other magical staff.
There are many obelisks scattered across Gielinor that are used in crafting Eastern battlestaves. The water obelisk can be found in the Hollows, within Mort Myre Swamp. The quest Nature Spirit must be completed to enter the swamps. The metal obelisk is located beneath the Lava Maze, near the runite rock. It is guarded by level 64 poison spiders and 2 black dragons.
The earth obelisk can be found on the summit of White Wolf Mountain, protected by wolves ranging form level 25 to 73. The fire obelisk is located in TzHaar City, near the entrance to the TzHaar fight cave. The wood obelisk is found in the elven region of Isafdar, and so requires the completion of Regicide to access. It is located next to the yew tree, east of Tyras Camp guarded by many fiendish traps.
Tokaji • Bamboo Forest • Forestry Guild • Mikyo • Eastern Shrine • Forest of No Return • Shikado • Assikai • Ganpon • Sorcerers' Tower • Farming Guild • Satezma • Naishi • Gujriki Stronghold • Mages' Outpost • Dragontooth Island Dungeon