As for the Assassin, it does not appear to show it as having the use MP for critical hits and testing it here it's not doing it, so that's strange I'll look into it further. Perhaps he had a 2nd weapon equipped that allows for use MP for critical hits? I'm not sure what though at that point in the game. Looking at the weapons here I have a bunch, probably too many weapons that have this trait...
And I also see the Ninja Knife appearing in the inventory here,
actually one right before the Burning House, and a second one right before the Lava Demon battle. I am removing his equipment when he takes off before the burning house, because I added in some code to place the best equipment on Oboro before the Lava Demon fight and for whatever reason it spits out another Ninja Knife afterwords like he had it equipped. I'm not sure why I'd remove his equipment though before the burning house, that's kinda silly and seems to might be causing this error of the one appearing right before the Lava Demon. Anyways I'll report back when I can answer for certain.
EDIT:
Not sure exactly what was happening, but now it's more or less fixed by not removing his equipment before the Burning House. It will instead remove his equipment right before the Lava Demon and equip him with the optimum gear, just because the player has no chance to do this themselves before that battle, in case they had him with nothing or crappy gear. I didn't choose to remove his gear afterwords, because Oboro is a bastard like that and keeps the gear and leaves!
This post has been edited by Gi Nattak: 22 June 2015 - 12:54 PM