The embodiment of malice itself rose from the darkness.
An incident suddenly erupts in Daybreak Town, where Horobi, Jin, Naki, and Ikazuchi are based! Something the likes of which no one has ever seen before is about to be created! Something so wicked that it exceeds human knowledge! Meanwhile, Aruto, who is holding on to his dream that Horobi can become a father, becomes aware of the development of a new kind of artificial intelligence technology that can only be developed by Hiden Manufacturing! It was just then when Aruto noticed Fuwa looking in…
Episode Tropes:
- Blatant Lies: Fuwa, when caught in a line to a fortune teller, just straight up pretends that there's isn't a line. The line that he's standing in.
- The Bus Came Back: Hakase Bot is brought back by Aruto in order to help him create the Friend Model AI.
- Call-Back: Once again, both Yua and Fuwa are harmed through the chip in her head, by Ark-Zero.
- Cross-Referenced Titles: The episode title is a callback to the first, 17th, and 30th episodes of the series.
- Curb-Stomp Battle: As soon as the Ark goes back into Horobi, it instantly beats Aruto by blasting him with a powered-up Attache Arrow. Needless to say, the Ark is absolutely terrifying.
- The Dreaded: When the Ark finally makes its presence known to Yua and Jin by possessing Horobi, followed by its transformation into Ark-Zero, Yua is downright terrified of the mechanical monstrosity she and Jin face off against. Notably, she begs Aruto not to fight the Ark.
- "Eureka!" Moment: Aruto has one for his idea for the Friend Model AI once he realizes Fuwa might just want someone to talk to.
- Evil Counterpart: Not only is Ark-Zero the polar opposite of Zero-One, even the title itself darkly reflects the first episode of the show.
- Foreshadowing: When Aruto tries to convince Horobi to fight back from Ark's possession, Ark-Zero notably responds "What are you talking about?". It's an odd response until you see the Wham Shot below.
- Get a Hold of Yourself, Man!: When Yua is terrified, speechless, and depressed at the sight and power of Kamen Rider Ark-Zero, the monster she created, Jin snaps her out of her depression with the following gem:Jin: "Get a hold of yourself! We should carry out our justice now!"
- Except that Jin didn't even bother punching Yua while doing so.
- Gone Horribly Right: In order to take down Ark once and for all, Jin recruited Yua to join his cause. Instead, they both became Unwitting Instigators Of Doom when they release Naki from Fuwa, as it led to the revival of the Ark. From there, the Ark turns the tides by taking Metsubojinrai.net's Singularity data, creating its own Rider form, and instantly curb-stomping Zero-One and Vulcan the moment it showed its true power. To say that the Ark is a monster would be a massive Understatement.
- Heads I Win, Tails You Lose: The Ark's attempted possession of Fuwa ends up being this, as win or lose, he takes out one of Zero-One's allies and grows strong enough to handle him as MetalCluster Hopper.
- Hope Spot: Both Zero-One and Vulcan overwhelm Ark-Zero during their bout, not even giving him a chance to retaliate as they destroy him with a Element Rampage Blast/Final Slash combo. Then the explosion clears, and its goes immediately downhill for the two from there.
- I Let You Win: Its implied from the Ark's statement that he let Zero-One and Vulcan defeat him so easily simply because he wanted to see their reactions that they were fighting (and harming) Jin. Once he repossesses Horobi's body for a second round, he easily tanks MetalCluster Hopper's attacks.
- It's All My Fault: Yua ultimately breaks down and blames herself for fully reviving the Ark, because she worked with Metsuboujinrai.net and removed Naki from Fuwa's chip, making its revival possible. Fuwa assures her that it’s alright, while Aruto admits to taking some of the blame for letting Horobi take Ikazuchi's Progrise Key in the first place.
- Kick the Dog: Three times, all courtesy of the Ark.
- When he first possesses Horobi, Naki ends up being damaged by the blowback and debris, necessitating a repair.
- After he detransforms Yua with his All Extinction, he cruelly inflicts pain through her chip as he slowly walks up to her. He does it again on Fuwa before he fights both Aruto and Fuwa.
- It's implied that he let Zero-One and Vulcan defeat him so easily the first time because it was harming Jin, the one who planned to kill him and their ally, in the process.
- Mood Whiplash: Happens a lot in this episode, namely going from Fuwa's attempted reading with Higashishinagawa no Haha to… the Ark violently possessing Horobi, injuring Naki in the process, and his first horrific, scream-filled transformation into Ark-Zero.
- Once More, with Clarity: We finally see what Jin said to convince Yua to remove Naki from Fuwa's head back in episode 34.
- Pet the Dog: Ikazuchi calls out Naki's name and goes to them when they're injured by the Ark's violent possession of Horobi.
- The Starscream: It's revealed that Jin's sudden compliance to MetsubouJinrai.net was, in fact, a plan to destroy the Ark, thus ending both MetsubouJinrai.net and ZAIA's plans in one fell swoop. Unfortunately, not only was the Ark completely aware about Jin's treachery, he underestimated how powerful the Ark would be.
- Shared Family Quirks: All of the Fuwa family share the same sense of humor.
- Ungrateful Bastard: Horobi, despite being a loyalist for a long time towards the Ark, is treated solely as a vessel for Ark to manifest itself in the real world.
- Wham Shot: Crossing over with Red Herring. Both Aruto and the viewers are initially led to believe that Horobi is the Ark's vessel… only for it to be revealed to be Jin. Worse is that the Ark can freely move between all of the MetsubouJinrai.NET members.
- The Worf Effect: Despite Ark-Zero facing two consecutive Finishing Move from Zero-One and Vulcan in a row, it's proven to be useless as Ark can just Body Surf to other members of MetsubouJinrai.net.
