by etony33 » Thu Nov 23, 2017 4:06 am
The catalyst for their change in dialogue (and music, and random encounters) is changing the legendary weapons into the Nei weapons. So, presumably, Dark Force is already in the Lashute dungeon if you go there after getting the sword but before the weapons undergoing the transformation.
It really is quite interesting. There's so much in that game that wasn't explored in detail, leaving everyone to speculate.