Recommended stats: 50+ Range
Required stats: 53 theiving
Required items: Mage shortbow, Cake (You get during the quest.) This is not tradeable by the way.
Okay, First step. Go to Catherby and talk to King Arthur.
He asks you to go steal a cake. This is why you need 53 theiving.
So walk to ardougne and steal the cake from this stall.
Then walk back to arthur and give him his cake. After this he will ask you for a mage short, give it to him. Don't have a pic for this lol, accidentally skipped it. But it is pretty obvious, and probably doesn't require one. So after that, he will ask you if you are ready for battle.
Say no and go get your gear from the bank. This inventory and items I suggest. Use rune arrows, the amount varies on your range level.
Yes, I drew a dude guy thing on there. So when you have your stuff, go back and talk to him and tell him you are ready. He will then teleport you to dessous. What you need to do is attack him and run back to this safespot quickly.
So after you kill him, you go to kamil. Attack kamil and run back to here.
Then Fareed. His safe spot varies, as the other 3 do too, depending on which one exactly you attack, it will be pretty close though.
If you followed this guide correctly, you should have beaten Desert Treasure!