He also didn't think that we would be able to take down
single-handedly Gaius and the Ultima Weapon. But like every good
villain worth his salt, he can
easily and simply adjust his plan to compensate for changed circumstances. (I really need to stop going on that site

).
It definitely seems like his new goal is not to defeat us (as he knows that's no longer a possibility), but instead to
break us and bend us to his will. And given the precedent going back to version 1.0 and Minfilia's comments about "the shameful truth" found "at the end of the Path" (as in, mastery of the Echo), this may be his end game.