Need Location Ideas

Okay yall...I am writing a new quest. The basic storyline involves a hugely powerful demi-god demon named Kharagan the Vicious

According to my lore he led a massive army into the fray during the godwars and reaked havoc...he never allied himself to any god but would be considered Chaotic Evil. He was eventually defeated by a joint effort...many parties literally ripped him apart...and bound his pieces in different locations all across Gielinor

I need locations that seem proper(this is the main purpose of this request)...If you want to write a synopsis of the challenge feel free

Eventually you will be rewarded with a new spellbook

The sections are: Bone, Fog, Magma, ????

these will each have several spells based on that element (not all combat spells)

Current Locations

-Jiggig
-Legends dungeon
-Underground Pass/nearby cavern
-Haunted Woods
-Mort Myre
-Observatory
-Trollweiss
-East end of light house island
-Fire Giant Dungeon in deep wildy (maybe)
-SE Varrock Quarry
-Snape Grass/Hobgoblin Peninsula