Before I start, I will confess that I am NO expert in end game theory crafting and all my character builds use SELF-FOUND or CRAFTED items that I acquire via the campaign mode. I have however been playing the game from its inception so I do consider myself somewhat skilled in character builds.
I have several characters in the 94+ range.
Most of them have been able to defeat Morgoneth in Elite, but were getting TOTALLED in Ultimate.
Surprisingly my Witchblade, which was my VERY FIRST character I ever started Grim Dawn with is now able to facetank Morgoneth with ease.
This character started off as most first time Grim Dawn players do as wanting to be a master of ALL skills. Throughout the years and learning from my other builds and with the items farmed, my old wonky Witchblade has suddenly become one of my more powerful characters, if some of my config seems suboptimal, or just looks crazy, it may mean that I have not yet found better stuff for my stash or that is just the way the character originally developed during play with items, skills, devotions etc.
I am not a fan of tuning a character’s setup just to take down a specific boss, either the character can kill the boss or not. I make notes of what bosses and nemesis my end game characters can comfortably handle and target them when I farm.
For example, this build wrecks Father Kymon and Korvaak in FG Ultimate and can facetank Fabious and Morgoneth with ease.
Not tested yet against other nemesis or bosses like Lokarr, but that is not a worry for me at the moment as I have another “Immortal Army” character that melts Lokarr, but she sadly withers in the face of Morgoneth and some of the other super bosses. My devastating Acid Sentinel can wipe out Kubucabra and Gargabol in seconds, but Lokarr kills her almost by just looking at her.
This is one of the great features of Grim Dawn whereby you can build a character that obliterates a super boss in seconds, but then fails miserably against some other bosses or areas. There is NO MAGIC SILVER BULLET - Always someone stronger, faster or more powerful than you 
Having a nice stable array of characters with different builds with notes of which each one can defeat which bosses and nemesis you are trying to farm is a great advantage as you really do not want to farm a super boss with a character that was designed to speed farm or clear mobs.
This is the build and look I have eventually ended up with for my starter Witchblade character “KANE”.
Many theory crafters may have lots of opinions and comments on it, but I can guarantee that you can stand face to face with Morgoneth and Fabious and bash away until they are dead. Works for me when I want to farm these guys.
