Monster Strike 2 special episode for Golden Week 2017.

"Change the world with music? Foolish."

Lucy's world stops after her band disbands. Meaningless days pass, until she meets her cousin Lucifer and his bandmate Ibaraki Doji. They ask her to join their indie band, the "Wicked Pistols".

Lucifer talks about his dream of going major after winning the MONSTERS ROCK competition, only for Lucy to reject him outright. However, Lucy's heart begins to thaw after a certain event...

(Source: XFLAG via ANN)

The second season of Monster Strike. 
 
Monsters are just a daily fixture of life these days. Ren, Aoi, Akira, and Minami have taken it upon themselves to clear the neighborhood of violent monsters. Days pass, until a transfer student from America, Mana Livingston, appears in their class. Mana quickly becomes a friend as the gang bond over their monsters. But a creeping shadow begins to lurk in the darkness, a harbinger of the danger to come. A new chapter of Monster Strike is about to be written! 
 
(Source: Crunchyroll) 
 
Includes episode 0.

When D'Artagnan went to Tokyo for a little fun, she spotted an unforgetable sight: Lucifer singing while basking in moonlight in a park. From that moment, no matter if she was asleep or awake, D'Artagnan's heart would not stop throbbing for some reason. 

One day, D'Artagnan sees a concert by the popular idol act Angely Diva at her friend Izumo's invitation. There, she resolved to follow her idol dreams, and the story of song and miracles begins.
 
(Source: Anime News Network)

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