This article is about a/an episode in Kamen Rider Zero-One.
Red alert WARNING: This episode contains scenes of character death. Viewer discretion is advised!

That is a Heart (ソレが心 Sore ga Kokoro) is the forty-third episode of Kamen Rider Zero-One. It features Aruto's first proper transformation into Kamen Rider Ark-One, the destruction of the ZAIA Thousandriver, the first appearance of the unfinished Ark Scorpion Progrisekey, and the second death of Jin.


Ironically, it was none other than Aruto who proved that "As long as the malice of humanity exists, the Ark will never die"! After the intense fight against Horobi spurring the destruction of humanity, Izu's loss triggers Aruto's uncontrollable desire for revenge! In order to prevent the escalation of the conflict between Aruto and Horobi, the other Kamen Riders start to make their move! However, such a conclusion can also lead to a great tragedy...


to be added


Guest Cast

Suit Actors

Forms and Collectibles Used


  • Key Used:
    • Vulcan
      • Rampage Gatling
    • Valkyrie
      • Lightning Hornet
    • Jin
      • Burning Falcon
    • Horobi
      • Sting Scorpion
    • Thouser
      • Amazing Caucasus
    • Ark-One
      • Ark-One
  • Form Used:
    • Vulcan
      • RampageVulcan
    • Valkyrie
      • Lightning Hornet
    • Jin
      • Burning Falcon
    • Horobi
      • Sting Scorpion


  • Key Used:
    • Thouser
      • Awaking Arsino


  • to be added


Zero-One Ep 43 Closing Screen
  • Closing Screen Progrisekeys:
    • Kamen Riders: Horobi
    • Progrisekeys: Incomplete Ark Scorpion Progrisekey (multiple)
  • Count at episode end
    • Progrisekeys in Zero-Two/Ark-One's possession: Rising Hopper, Biting Shark, Flying Falcon, Flaming Tiger, Freezing Bear, Breaking Mammoth, Shining Hopper, Hopping Kangaroo, MetalCluster Hopper, Zero-Two, Ark-One
    • Progrisekeys in Vulcan's possession: Shooting Wolf, Punching Kong, Gatling Hedgehog, Trapping Spider, Assault Wolf, Rampage Gatling
    • Progrisekeys in Valkyrie's possession: Rushing Cheetah, Lightning Hornet, Fighting Jackal
    • Progrisekeys in Jin's possession: Burning Falcon
    • Progrisekeys in Horobi's possession: Sting Scorpion,
    • Progrisekeys in Thouser's possession: Amazing Caucasus, Sparking Giraffe, Exciting Stag, Crushing Buffalo, Splashing Whale, Dynamaiting Lion, Storming Penguin, Scouting Panda
    • Progrisekeys in Azu's possession: Ark Scorpion (incomplete)
    • Humagear Progrisekeys in Zero-Two/Ark-One's possession: Is, Uchuyaro Subaru, Saikyo Takumi Oyakata, Dr. Omigoto, Sumida Smile, Mamoru, Bengoshi Bingo, Ikkan Nigiro, Okureru, Matsuda Enji, G-Pen, Matsurida Z, Fukkinhoukai Taro, Shesta, Delmo, Love-chan
    • Humagear Progrisekeys in's possession: Uchuyaro Raiden
    • Zetsumerisekeys in Thouser's possession: Awaking Arsino
    • Zetsumerisekeys in Ikazuchi's possession: Dodo
    • Zetsumerisekeys in Naki's possession: Japanese Wolf
    • Zetsumerisekeys in's possession: Berotha, Kuehne, Ekal, Neohi, Onycho, Vicarya, Gaeru, Mammoth, Arsino
  • This episode marks the final TV appearance of Kamen Riders Thouser and Valkyrie.
  • This episode features the second death of Jin after his first death in episode 16.
  • This episode also marks the only and final appearance of Gai Amatsu as Kamen Rider Thouser since episode 39.
  • This is the first episode not to feature Zero-Two since its debut in episode 40.
    • This is also the first episode not to feature any form of Zero-One at all, discounting the footage of Zero-One that was displayed via Gai's ZAIA Spec.
  • This is the only time RampageVulcan performs a standard finisher without using the powers of Rider Models.
  • This episode features the final appearance of RampageVulcan, Valkyrie Lighting Hornet and Jin Burning Falcon.
  • Izu does not appear in this episode since her debut in episode 1.

External links


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