Runescape doesn't do a great job of flowy capes and robes. That seems like the biggest hurdle to me. The rest you could come up with some reasonable approximations, and doesn't seem terribly hard even, so I am guessing you wanted help with the robe most of all. The staff I'd say looks a bit like The polypore, possibly one of the runic staves or maybe even the slayer staff. I'm not that familiar with the character though so I'm just going off google images.
Cheers!
11-Oct-2017 06:26:52