This is a partial character sheet for Kamen Rider Build. Visit here for the main character index. Subjective trope and audience reactions should go on the YMMV page.
The most battle-hungry of the three nations, they readily accept the Pretext for War provided by Gentoku and invade Touto in episode 16, seeking control of the Pandora Box.
- Book Dumb: Many of the citizens pulled their children out of school due to the economic collapse. Thankfully, certain individuals such as Kyoka Katsuragi begun free volunteer schooling for kids.
- Deadly Upgrade: Undergoing a procedure using the Hazard Trigger upgrades the Hokuto Crows Trio's monster forms from Hard Smash to Hazard Smash, granting them even greater power and a black-repainted costume. The procedure itself is so agonizing as to leave the recipient bedridden, and the side-effect is akin to becoming a Necro-Over: the removal of the usual safety net that allows characters to just turn back into their human forms when beaten in their transformed state.
- Elite Mook: Rather than creating their own Riders from scratch, Hokuto's branch of Faust has continued to improve on Smash, leading to the creation of Hard Smash. These are much stronger, fully sentient, and can control their transformation, a la past series' elite monsters, with the first three proving more than a match in battle for Build Driver users. By episode 20, Hokuto has begun gearing up for their mass-production, although with Hokuto's conquest by Seito and Seito's preference for the Kaiser System instead of Smash, this never comes to pass.
- Faction Calculus: The Subversive faction, with four named characters on their side in the war to Touto's two and Seito's three. Their Hard Smashes are more powerful than the standard kind, but easily surpassed by the Sclash Driver or even the Build Driver with certain Best Matches. Like many Subversive factions, they also fare worse the longer the war draws out.
- Government Conspiracy: While Hokuto claims to emphasize social programs, they've actually poured almost all of their national budget into military development. Even before Gentoku gave them an excuse, Hokuto was the most ready and eager of the three nations for war.
- Mecha-Mook: Not surprisingly, they have their own army of Guardians, with some added armor that doesn't stop them from getting trashed just as easily.
Portrayed by: Ryoko Gi
- Attack! Attack! Attack!: Her national strategy as a whole relies on a quick, decisive war due to Hokuto's ruined economic output and pouring all of its resources into its military.
- Big-Bad Ensemble: After spending most of the first arc looking for an excuse, Gentoku's actions finally give Yoshiko the cover she needs to declare war on Touto, shifting the focus of the series away from Touto's internal power struggles and towards the war that defines the next arc. She also has ties with Blood Stalk, who gave her the information on the Sclash Driver, and recreated it to allow one of her soldiers to become Kamen Rider Grease. She's taken out of the running in episode 22 when her over-eagerness leads to Hokuto's conquest by Seito.
- Evil Is Hammy: Once her true colors are revealed and the war arc begins, she takes to full-on Laughing Mad supervillainy. Nothing short of Rita Repulsa comes to mind.
- Hate Plague: Similarly to Gentoku and the other regional leaders minus Taizan, Pandoras Box has influenced her to the point where gaining control of the power of the Pandora Box, and with it rulership of all of Japan, have become her main focus instead of providing for her citizens.
- Hoist by His Own Petard: From her to another villain - Masakuni Mido, Seito's Prime Minister. Her attempt to take over Touto regardless of the representative match's outcome leaves her country powerless to stop Seito's invansion.
- My God, What Have I Done?: Her first reaction upon being cured of the Pandora Box's Hate Plague is remorse and shock over her actions.
- President Evil: Well Prime Minister Evil, but she fits the archetype of being the elected leader of a country with sinister ambitions.
- Put on a Bus: After Rogue walks into her office with his hand buried knuckle-deep in the face of one of her guards, Tajimi disappears and her fate isn't mentioned. It was reasonable to assume she'd died, but...
- The Bus Came Back: Episode 40 shows her finally making a comeback after being gone for nearly half the show as the first Lost Smash.
- Sanity Strengthening: The Genius Bottle reverting her from a Lost Smash also cures her of the Pandora Box's Hate Plague.
- Sore Loser: Plans to betray her deal with Taizan and invade Touto with all of her Guardian forces if the representative duel doesn't go her way. This promptly bites her in the ass due to leaving no forces to protect herself against Seito.
Portrayed by: Kouhei Takeda (live), Satoshi Fujita (suit)
Hokutos first Kamen Rider as a result of the leaders alliance with Blood Stalk, who gave them a Sclash Driver and the means to make the Robot Sclashjelly. He's a government-funded assassin.
See his page in Kamen Rider Build Protagonists
Akaba / Masaru Ooyama
Portrayed by: Eishin (live), Yuji Nakata (suit)
- The Brute: Kazumi describes him as the dumbest guy he knows, and given he knows Banjou, that's saying something.
- Colourful Theme Naming: The red member of the Hokuto Three Crows, named for the color red. Episode 20 reveals that it's deliberate: Akaba is just a codename. His real name is Masaru Ooyama.
- Eye Beams: His ability as the Castle Hard/Hazard Smash. It's incredibly powerful, so to keep things balanced he's often stopped just before he can fire it either by his enemies or his allies as a bit of a Running Gag. In total he only gets to fire it twice.
- Japanese Delinquents: He wears a bandana, has Delinquent Hair, has powerful weapons, and loves causing mindless destruction.
- Killed Off for Real: Dies at the hands of Kamen Rider Rogue in Episode 25.
- Luckily, My Shield Will Protect Me: He wields two Ground Ramparts as Castle Hard Smash. He can either use them to defend himself or ram at the enemy.
- Mighty Glacier: Unless he's doing one of his special moves or is participating in the group's combination attack, he's the slowest out of the three while boasting absurdly high offensive power.
- Meaningful Name: His name translates as red wings and aside from his color scheme, he is part of Hokuto Three Crows. His surname means "big mountain".
- Roaring Rampage of Revenge: Following Aoba's death, he tries to run in and attack Sento barehanded. He and Kiba are stopped by Kazumi.
- Sole Survivor: Masaru lasts two episodes longer than either of his companions.
- So Proud of You: Of the three, Masaru was the one Kazumi was proud of the most.
Aoba / Syuuya Aikawa
Portrayed by: Tateto Serizawa (live), Kotaro Kaji (suit)
- Animal Motif: Stag Beetle
- Colourful Theme Naming: The blue member of the Hokuto Three Crows, named for the color blue. Episode 20 reveals that it's deliberate: Aoba is just a codename.
- The Comically Serious: Aoba is more focused on the task than his peers, but unwillingly participates with his teammates antics.
- Dual Wielding: Wields a pair of swords called Rapture Scissors.
- Killed Off for Real: The victim of RabbitTank Hazard's first rampage.
- Sarcastic Clapping: The way he mocks Sento and Misora's emotional moment in #17.
- Super Speed: He can dash with intense swiftness for short bursts.
- Meaningful Name: His name translates as blue wings and aside from his color scheme, he is part of Hokuto Three Crows.
- Used To Be A Sweet Guy: According to Kazumi, Aoba was someone who cared about his friends and would cry for even a complete stranger before the war.
Kiba / Syoukichi Mihara
Potrayed by: Takuya Yoshimura (live), Hajime Kanzaki (suit)
- Animal Motif: Owl.
- Colorful Theme Naming: The yellow member of the Hokuto Three Crows, named for the color yellow. Episode 20 reveals that it's deliberate: Kiba is just a codename.
- Forgot I Could Fly: When Grease uses the Helicopter bottle to make his escape in #19, he's the second of the trio to grab onto his leg to join him even though he can fly independently.
- Heroic Sacrifice: Saved Kazumi from getting killed by the Engine and Remocon Bros' attack by getting in the way.
- Jerkass: Somewhat low key due to his Keet tendencies, but still visible when he mocks Sento and Misora's emotional moment in #17. He does, however, have a heart deep down.
- Keet: Hes much younger and excitable than his peers, especially after watching the battle between Kamen Rider Build and Hokutos ordinary Smash.
- Killed Off for Real: In #23 by taking a Funky Shot meant for Kazumi.
- Psychopathic Manchild: He's obscenely childish, to the point of throwing a fit when he got beaten once. He's also very violent and is part of an elite military group.
- Meaningful Name: His name translates as yellow wings, and aside from his color scheme, he is part of Hokuto Three Crows.
- Roaring Rampage of Revenge: Following Aoba's death, he tries to run in and attack Sento barehanded. He and Akaba are stopped by Kazumi.
- Taking the Bullet: See Heroic Sacrifice.
- Weak, but Skilled: Of the Hokuto Three Crows, he has the lowest Hazard Level at 3.6 (the other two are at 3.7). However, he is able to handle the Kamen Riders with no problems.