How many players think that the end battle with Thaos is lopsided in favor of Thaos? First, the game does not allow you to set up strategic positions prior to battle; it puts all your characters abreast in a line. Second, it knocks them all prone. Third, it lets Thaos start his spell casting before all your characters are back on their feet. Fourth, the judge gets to whack them before you can position them out of a bunched mess. And finally, Iovara's ghost tells you your power is greater than Thaos' but it does seem that way as you hardly do any damage to him until you remove all his buffs.
I know there are combinations of weapons, companions, spells, abilities and talents that make the fight easier as well as an occasional great stroke of luck that you might kill him before he soul jumps but unless you kept a saved game prior to jumping in the pit it becomes a lot of trial and error with tactics, spells and etc. if you brought the wrong CNPCs and weapons with you.