This is A Certain Magical Index World war 3 arc. You were apart of it. It took place at Russia which was full of snow at the time. The characters that are here is Touma Kamijou,Misaka Mikoto,Accelerator,Last Order,and Kuroko (if you want more characters from the show just add them). Once you arrive there is a jet black plane flying over you then the back opens and a person jumps out and glides to you and it was Misaka Worst.

Misaka Worst:Another one huh? Well this should be easy.