his guide was made and has been used by me to complete desert treasure quest on a 1 def and pray acount.
35+ hp reccomented
Quest Items needed/recommended
Magic shortbow (buy from shop at varrock)
Cake (steal from ardgougne baker stall / 53 thieving [thanks reaper])
You can start this quest by teleporting to Varrock, and having a chatter with the king arthur
which can be found at varrock caste.
screenshot from a friend.
he asks you to fetch him a cake. so off you trot and forfill his deed. walk/run Or Teleport to ardougne and steal a cake (56 thieving)
teleport back to catherby and speak to him once again. he then asks you to fetch him a Magic Shortbow. (Buy From Shop at Varrock)
once you have obtained this, speak to him once again and he will ask do you are you ready to fight the 4 boss's. say no and get your fighting equipment ready(read on for suggestions)
then once you have defeated the four boss's the quest is complete.
to see the safe spots for the four boss's look at the images underneath and enjoy.
I would recommend for a cheap approach a mage shortbow and range armour + 1000 iron arrows or 500 mith/addy/rune.
The quicker, but more expensive way is using a rune crossbow and about 600-1000 rune bolts.
I would recommend the best magic robes that you can weild and a autocasting staff would help.
500/1000 wind blast or higher spells, depending on your magic level
Now i will reveal the safe spots for each NPC that you have to fight for the quest
Starting with dessous, attack him and follow the black arrow, to get him to get stuck. (or attack and run to swamp , it will stop near the exit.)
Now for kamil, this one is hard to get him. stand on the hill then attack him and he should stay there. also if he goes to far east you have to kill him again.
Last but not least fareed. simple attack the one on the west and run to that spot. he gets stuck easily.
And finaly Damis. simple attack him and run north, he just stops just after the pillars.
sorry for any typo's