This guide has worked for me one the 1 single occasion I have given it a try

But it was a long time ago and it worked well !
That being said, It is a great guide and I can't find anything significant in updates that would affect the guide. Tactics seem to be the
key and making sure to do the harder quests (Four Horsemen) & fighting King Frozenwind can be a pain with all those Meteor showers!
Have patience though and all will be well