The only update Ardyn got was adding some of his moves from Verses 1 and 2 of Episode Ignis, the marital arts and laser beam so far.
Tbh i don't mind it that much imo, the thought of Ardyn getting a monster form as an additional phase just feels like it would have cheapened the whole point of Noctis fighting and slaying a bitter human-being for the sake of a JRPG trope. I mean i can get wanting more of a challenge/climax, but not if it meant downplaying how personal Ardyn was with Noctis.
And besides, i'd prefer the PE dialogue solution anyway.
And besides, i'd prefer the PE dialogue solution anyway.