Months have passed since Kamen Rider Birthright defeated the Over Quartzer along with his Titan Guardian Athar. Now Percy decides to travel back to America along with his girlfriend Ryuko and her friends to celebrate Halloween. Unbeknownst to them...
(Percy and his group prepare to fight as Samhain uses his vines to grab and throw Mako and her family out of the battlefield.)
Mako: PERCY!
Samhain: This is the end for you.
Ryuko: (draws her blade) Face us, if you dare!
Philis: (raises his hand) No. (steps forward) He's mine.
(Philis and Samhain charge at each other as they use their magics and fire magic blasts at each other as they fly and Samhain uses his vine whip at Philis, who blocks his attacks, but the Halloween Overlord overpowers him.)
Philis: NITECORE, I NEED YOU!
(Nitecore blows a fireball at Samhain, blasting him away.)
Samhain: Good. Very good.
(Ryuko charges at Samhain, but gets grabbed, and thrown to the wall as Satsuki and the Elite Four try a sneak attack, but Samhain uses his dark magic to shove them as he whips Philis' legs and cheek before pushing him with a flamethower. Percy decides to transform as he charges at Samhain.)
Percy: Henshin!
TRUTH! JUSTICE! THE AMERICAN WAY! KAMEN RIDER BIRTHRIGHT!
(He flies towards Samhain, who grabs him and slams him down.)
Samhain: You really gotta stop meddling where you're not called.
(Then Samhain chants a dark spell and prepares to kill Birthright, but then Philis gets in the way and takes the hit instead as he weakly chants his last spell, turning Nitecore into golden particles as they approach Birthright, much to everyone's confusion. As the golden particles envelop him, a transformation sound is heard.)
HAPPY HALLOWEEN! THIS IS HALLOWEEN! KAMEN RIDER HALLOWRIGHT!
(Kamen Rider Birthright then changes to a vampiric-like form, and his eagle trinket becomes a dragon trinket, courtesy of Nitecore.)
Oops! This image does not follow our content guidelines. To continue publishing, please remove it or upload a different image.
Hallowright: Trick or Treat. (does a Dracula pose) Say hello to Kamen Rider Hallowright!
(Ryuko, Satsuki and the Elite Four get shocked by his new Kamen Rider Form, and so is Samhain. Suddenly four portals open up behind Hallowright.)
(As the screen fades out, a Kamen Rider and an Ultra come in holding a "To be continued" signal as the Ultra carries it and flies away with the Kamen Rider hopping on its leg.)
