In the quest when you reach the sentinels you can run under the sentinel on the east side and stand against the rock wall. If you do this then the daggonath you are under will not attack you or heal its friend and you can range the other sentinel and only have to deal with its attacks.

good to know...

im not exactly sure but this doesnt count as bug abuse right?

Many monsters have flaws in them that have remained unchanged for many years, so we'll wait for Jagex to decide. I've added it to the guide, as it is a great tip, and if Jagex changes it, we'll edit it out :)

Thanks so much! You've been credited!