Are the move tutors have limited availability? Or they can be used infinite times?
Is the breeding in this game following Gen5 or Gen6 rule, or custom rule?
Is Scizorite, Gardevoirite, and Galladite available in Purity run? I recalled that only Delta versions of them are available on normal mode.
Is there any exclusives between Lighter story and Darker story beside that one Potion?
Concerning, East Will, maybe it is dangerous to change the story inbetween because that item can only be obtained much latter in Lighter story. If I changed to Darker story after 3rd gym, I’m afraid to miss it. Is there any item that works like that?
I believe it’s mostly Gen VI minus the fact that you can still pass down TM moves through breeding. So it’s technically custom; you can see the mechanics here: Breeding Mechanics - The Pokemon Insurgence Wiki
AFAIK these are still all Delta Mega Stones on Purity mode. Yeah, that and a few other things were a bit of an oversight.
I haven’t played through Light story mode past the Cult of Darkrai base unfortunately. I’m leaning more towards the answer being no, though.
I don’t think there is. I think suze set the game to put the Will there by default when switching between modes. I only say this because we’ve had dozens of reports and questions from people that have found the Will further up the Tower even though they had already gotten it once already.