Get a Dark Summ and be a failure having level 500 in Normal World. It'll take a long time but you can kill them :P Just make sure to kill Deis first (unless you're okay with the Iron Golem summons) kill Troy second (unless Seso is pissing you off) and leave Seso for last, unless Seso is pissing your off unusually often. (Not sure the Tranquility heal, but the Holy Light "thing" is like 20k HP. You save her for last due to highest armor [by far] and also has Frost Armor)
Try using Medean Curse (mostly for the evade, but -1k armor lasts through Divine), Leech Shield (only for melee and for giggles lol, kill Troy first if using this), Minotaur Axe (if you don't care about the -1k armor, try dropping it to lower armor then attack them), Broken Scepter (for the Blink), Savior Armor (it saves you lol), Iron Golem Fist (you NEED this, Crit Fury MIGHT work as replacement), and Cheese Shield (if not using Leech Shield, I'd say have Leech if Troy is dead, especially if you're melee. +15% vamp & they deal less damage)
The biggest problems with Goddesses are their spells & their Berserker's Blood Lusts. Between Deis's Summons, (I think it's Deis's) Curse, Troy's Voodoo, and Seso's Heals, almost impossible. (Anytime Troy uses Voodoo while Seso uses Tranq or if Deis does lightning/quake, don't hit Troy.)
If all else fails, make a RG and a PR. RG goes tank pure setup (with spell resist too) and PR goes pure dps (but with Lightning Shield or something to keep damage taken low).
Or, just go online with 1/them and join a game where someone goes roflpwn on the Goddesses, snag the Auras, and make the mix. I'm over level 900 and still have Aura of Gods, I find it that useful. Getting to Chaotic in like 5-6 minutes....simple. (Like 10 by the time people load/stupid intro screen.)
Yet, I digress....