Several really fun and interesting new mechanics, those being the new reward multiplier thing when collecting items, and the special weapons for each character. All of the weapons feel very different from eachother and bring entirely different ways to play with them. (For Marisa however the only different way to play is not playing, her unique weapon kinda sucks sadly. MarisaC from MoF was not missed.) Playable Sakuya is always really good for bonus points too, thanks ZUN. Fun bosses, interesting themes, and a return to independent incidents. Overall, a very fun game.
Primordial Beat~Pristine Beat is one of my favorite themes for the series, really damn good and love the percussion for once, definitely a standout for the soundtrack of this game. I know I said fun bosses but god I couldn't go without talking about Seija. Flips your damn screen and shoves you in a washing machine. The fight is a bit scary but it's still honestly pretty fun and is very unique, out of the large pool of unique stage 5 bossfights.