Truly magnificent! Nothing compared to the first season and I can definitely see why:
Character development!
Not only does this season take a significantly darker tone that really does Mikoto justice as a heroine, it truly manages to deliver a stunning, absolutely emotional retelling of the sisters arc from Toaru Majutsu no Index S1 . Mikoto's interaction with Touma receives a beautiful and emotional makeover compared to the latter and you get to see the Mikoto's sweet, vulnerable side. After that it is IMPOSSIBLE not to fall in love with her character and appreciate her as a heroine.
Unfortunately I cannot give this more than 8 because FRANKLY I didn't care about anything that happened after episode 17. I guess the one thing I enjoyed during those last episodes was seeing Mikoto ''grow up'' as a person.
Definitely, DEFINITELY a must see! ONCE again watch this according to "Full chronological order" available on reddit!