This article is about a/an Rider in Kamen Rider Build.

"The fire of my heart...passion..."
―Kazumi's creed for fighting.[src]

"Fan the flame and crush everything!"
―Kazumi catchphrase before fighting[src]

"Kamen Rider Grease...arrives."
―Kazumi's introduction to Build and Cross-Z.[src]

"This is it! This is the battle I wanted!"
―Kazumi's excitement in a fight under the influence of the Sclash Driver.[src]

Kazumi Sawatari (猿渡 一海 Sawatari Kazumi)[2] is a resident from Hokuto and the leader of the Hokuto Three Crows. In the earlier stages of the war, he was given a Sclash Driver and the Robot Sclashjelly to transform into Kamen Rider Grease (仮面ライダーグリス Kamen Raidā Gurisu), as the Rider representative of Hokuto.

Character History

According to Sawa's report, Kazumi was once the owner of his family's farm in Hokuto, with Akaba, Aoba and Kiba as his workers. However, as a result of the Sky Wall Disaster, virtually all the farmland in the region was rendered infertile. Rather than lay off his workers, Kazumi used his savings to help his employees and their families. Victory of Tears

One day, Kazumi came across a man named Massugu Ubukata, who was attempting to take his grandmother to a hospital only for his path to be blocked by Hokuto soldiers. Giving the soldiers a beating, Kazumi enabled Massugu to proceed, and his grandmother made a full recovery. Kamen Rider Build: Birth! KumaTelevi!! VS Kamen Rider Grease!

When Kazumi's resources were depleted, he willingly enlisted himself to be a test subject for Faust to futher insure his workers' survival. Kazumi tells Stalk, who was leading the experiment, to lie to the workers by informing them that Kazumi lost his memories as a side effect of the experiment. Victory of Tears

Shortly before Hokuto invaded Touto for the Pandora Box, Kazumi was chosen to lead a strike team in charge of retrieving Touto's Fullbottles and Pandora Box panels. He was given a Sclash Driver by Soichi Isurugi, allowing to become Kamen Rider Grease. Feeling indebted to their boss for his sacrifice, his three workers became Hard Smash, forming the rest of his strike team.

Indebted to Kazumi, Massugu Ubukata wished to join his side and as such, crafted dog tags for himself as well as Kazumi and the Hokuto Three Crows. However, Kazumi initially refused his gift and ask him to go back to Hokuto. Kamen Rider Build: Birth! KumaTelevi!! VS Kamen Rider Grease!

Hokuto-Touto War

Kamen Rider Grease stole the Phoenix and Robot Fullbottles from Sento. Kamen Rider Heisei Generations FINAL: Build & Ex-Aid with Legend Riders

As Kamen Rider Grease, Kazumi led the Hokuto advance into Touto once war was declared by Prime Minister Yoshiko Tajimi. Penetrating the Skywall, Grease destroyed many Touto Guardians. The Weaponry Hero

Ryuga Banjou encountered him as he searched for the Hokuto Three Crows. A Strong Smash Hazard appeared and began attacking bystanders, and as Ryuga put on the Build Driver, Kazumi destroyed the Smash in one punch using his hidden Helicopter Fullbottle before leaving. Later, after Ryuga and Sento had defeated the Hokuto Three Crows in Ryuga's first fight as Cross-Z Charge, Kazumi showed up to challenge them with his own Sclash Driver. Rider Wars Start

One fight with Cross-Z Charge was interrrupted by the Three Crows. Stating that they broke the rules, Kazumi relinquished the Kuma and Televi Fullbottles to Ryuga. He later caught up with Massugu Ubukata when he was defeated by Sento Kiryu, having exposed himself to Nebula Gas and becoming the Ice Smash. Engaging Build, Grease found himself bewildered by Sento's new KumaTelevi Best Match. Ultimately, however, Sento learnt the story of Massugu and Kazumi through Televi-san, and chose to return the Kuma and Televi Fullbottles to Kazumi. Left with Massugu, Kazumi realized that he was still holding on to the dog tags he had made for him and his comrades and finally accepted them, claiming that the jingling sound Massugu made when he walked irritated him. Kamen Rider Build: Birth! KumaTelevi!! VS Kamen Rider Grease!

Hokuto's Defeat

At The end of both rivalry between Hokuto and Touto, Build and Grease we're near the end of the war between their countries. At Hokuto would of stood the chance of defeating Touto, because Build was too afraid to use the Hazard Trigger, and would possibly forfeit the war, then Hokuto for the winning. Soon using the hazard trigger to defeat Kamen Rider Grease, Hokuto lost the war, but was lost to Touto after Build was using the hazard trigger for the only thing to end Hokuto and Touto's rampaging war. Victory of Tears

Seito's Uprising

After the ending of Hokuto and Touto's war against each other, it was soon that the two countries would have to endure, and fight Seito as their last battle with the countries. Soon after a total threat against the country of Hokuto, one of the Hokuto Three Crows decided to defend his people from the vanquish of Seito's Wrath, and was soon captured by the Washio Brothers, Kazumi had no other choice but to go back to Hokuto with Akaba by his side to escape, but failed to try and was shot down by Fu Washio. Then later sacrificing himself, Kiba gave his dog tag to Kazumi, and was force to regret the death of Kiba after sacrificing himself for Hokuto and Touto. The Phantom of the West

Seito-Touto War

As Seito and Touto war was soon to the beginning of the end, Grease had fought out Rai Washio during the battle of the two countries, and miraculously won the battle against Engine Bro's. Kazumi was sent to Hokuto to retrieve the Nabeshima Family out of Seito, while Sento and Sawa devised a plan to safely secure the Nabeshima Family, and end the war with Seito. The Genius Arrives With a Tank


Kazumi's demeanor alternates between calm and composed to ruthless and hysterical, depending on whether he's fighting or not. Presumably due to his usage of the Sclash Driver, Kazumi is obsessed with battle and finding a worthy opponent. He is not afraid to use lethal methods, going as far to even try to deliver a Rider Kick at an untransformed Banjou.

However, Kazumi operates by a certain code: he insists on not targeting civilians as long as they stay out of the way, and decided against taking Build's FullBottles due to him butting in the battle, much to the trio and the Hokuto Prime Minister's dismay. Kazumi is an avid fan of Mii-tan, allowing Sento and Banjou to escape and cancelled Akaba's attack, since Misora is the one who helped them. This also shown as he own a pillow with Mii-Tan picture as he moving to Nascita, much to Banjou's annoyance.

He also secretly cares about his underlings, as he is against the Prime Minister and Stalk's idea of giving the Three Crows more power by strengthening them with the Hazard Trigger, knowing that they will die after they are defeated. After the Three Crows become Hazard Smashes, Kazumi was visibly frustrated.

Having seen people die in front of him before, Kazumi recognizes the seriousness of war, viewing death to be a natural part of a war. Though he was deeply saddened by Aoba's death, he conceded that Aoba knew that his own life was going to be at stake, and that he died because he was weaker, though that did not change the fact that he was someone Kazumi cared about. While Kazumi bears no ill will towards Sento, he still resolved to have a fair fight with the latter that would be held in the proxy war between Touto and Hokuto.

Kazumi has a tendency to punctuate exaggerations when fighting.

Powers and Abilities

  • Hazard Level 4 Physiology: Kazumi has undergone an experiment from Faust which injected him with a certain amount of Nebula Gas. However, instead of mutating into a Smash, the gas retained his body without side affects (though he did feign memory loss in an attempt to distance himself from the Three Crows). His natural Hazard Level is much higher than most, as his Hazard Level starts at Level 4 during his introduction,allowing him to utilize the Sclash Driver to transform into Kamen Rider Grease. In Episode 19, Blood Stalk read his level, and it has risen to 4.2.
  • Fullbottle Augmentation: By using a Fullbottle in his hand without transforming, Kazumi can gain abilities based on said Fullbottle's traits:
    • Helicopter: Allows Kazumi to perform fiery punches. First used to defeat a Strong Smash Hazard.


  • Mii-Tan: Since Kazumi is a huge fan of Mii-tan, he quickly loses his will to fight and even allows his enemy to escape if Misora is the one who helped them. It's hinted that he might have a crush on Mii-tan, but when Akaba asked him about his apparent crush and the possibility of her being Sento's girlfriend, Kazumi denied it by claiming that Mii-Tan is everyone's idol. Kazumi also shown to be completely gullible when meeting his idol face to face, as he almost fell into Sawa's trick to spend his money just to get her handshake, much to Akaba and Kiba's annoyance.



Kamen Rider Grease

"Tsubureru! Nagareru! Afurederu! (epic orchestral music) Robot In Grease! Buraa!"
―Transformation announcement[src]

Rider Statistics

  • Rider Height: 203.0 cm
  • Rider Weight: 118.3 kg

Ability Perimeters:

  • Punching Power: 31.3 tons
  • Kicking Power: 34.3 tons
  • Maximum Jump Height: 54.0 m
  • Maximum Running Speed: 100 m. per 2.5 sec.

Grease's base form is accessed by inserting the Robot Sclashjelly into the Sclash Driver and pumping the lever.

Unlike Cross-Z Charge who has more punching power, Grease has more kicking power. Besides that, Grease shares similar stats with Cross-Z charge in terms of jumping power and speed.

Also, as he is presumably much more experienced with the Sclash Driver, he is able to fight against and defeat Cross-Z Charge at ease, even when the latter has similar power stats as him.

Grease's personal weapon is the Twin Breaker.

Grease has three different finishers:

  • Sclash Driver finisher:
    • Scrap Finish (スクラップフィニッシュ Sukurappu Finisshu):
      • Rider Kick: Grease uses his Machine Pack Shoulder (マシンパックショルダー Mashin Pakku Shorudā) to generate Variable Jelly (ヴァリアブルゼリー Variaburu Zerī) in order to propel himself forward as he delivers a powerful kick to the enemy, coated in gold energy.
      • Rider Punch: Using the Machine Splash Armory (マシンスプラッシュアーモリー Mashin Supurasshu Āmorī) on either of his hands, Grease performs a powerful punch with a Variable Jelly projection of the Demolition One.
      • Rider Shooting: In Ganbarizing arcade game, Grease fires four Robot Fullbottle insignia from his Machine Pack Shoulders and Robo Struggle Gloves (ロボストラグルグローブ Robo Sutoraguru Gurōbu) as they explode upon latching to his targets.
    • Charge Crash (チャージクラッシュ Chāji Kurasshu): Using the Machine Splash Armory on either of his hands, Grease can use the power of an Organic Fullbottle.
      • Kuma: Grease creates a pair of energy bear claws and crushes the enemy with them.
    • Discharge Crash (ディスチャージクラッシュ Disuchāji Kurasshu): Using the Machine Splash Armory on either of his hands, Grease can use the power of an Inorganic Fullbottle.
      • Lock: Grease creates chains that entangle enemy before attacking with a Variable Jelly projection of the Bind Master Key.
      • Helicopter: Grease creates a Variable Jelly projection of a three-bladed rotor, gaining the ability to fly.
      • Keshigomu: Grease creates a big eraser that allows him and/or his comrades to flee.
  • Twin Breaker finishers:
    • Beam Mode:
      • Single Finish (シングルフィニッシュ Shinguru Finisshu): Grease channels the energy of a Fullbottle or the Robot Sclashjelly and performs a powerful blast.
        • Fullbottle:
          • Gatling: Grease fires multiple balls of golden energy in rapid succession.
        • Sclashjelly:
          • Robot: Grease shoots the enemy with gold lightning in rapid succession.
      • Twin Finish (ツインフィニッシュ Tsuin Finisshu): Grease channels the energy of 2 Fullbottles or a Fullbottle and the Robot Sclashjelly and performs a powerful blast.
        • 2 Fullbottles:
          • Smapho + Televi: The Twin Breaker makes a test card-esque barrier, which switches into the image of three smartphones that launches energy "apps" projection.
        • Fullbottle + Sclashjelly:
          • Helicopter + Robot: Grease shoots the enemy with projections of gold helicopter rotors.
    • Attack Mode:
      • Single Break (シングルブレーク Shinguru Burēku): Grease channels the energy of a Fullbottle or the Robot Sclashjelly and performs a powerful stab.
        • Fullbottle:
        • Sclashjelly:
      • Twin Break (ツインブレイク Tsuin Burēku): Grease channels the energy of 2 Fullbottles or a Fullbottle and the Robot Sclashjelly and performs a powerful stab.
        • 2 Fullbottles:
        • Fullbottle + Sclashjelly:
  • Sclash Driver + Twin Breaker finisher: Grease can combine the powers of the Sclash Driver and the Twin Breaker to perform a powerful finisher. However, it puts a huge strain on Grease's body and cancels his transformation.
    • Scrap Finish/Twin Break (スクラップフィニッシュ/ツインブレイク Sukurappu Finisshu/Tsuin Burēku): With the Twin Breaker in Attack Mode, Grease channels the energy of 2 Fullbottles or a Fullbottle and the Robot Sclashjelly and performs a powerful stab.
      • 2 Fullbottles:
      • Fullbottle + Sclashjelly:
        • Robot + Robot: Grease covers himself in golden energy and performs a drill attack at the enemy. This finisher is capable of taking down a wall of a building.
    • Scrap Finish/Twin Finish (スクラップフィニッシュ/ツインフィニッシュ Sukurappu Finisshu/Tsuin Finisshu): With the Twin Breaker in Beam Mode, Grease channels the energy of 2 Fullbottles or a Fullbottle and the Robot Sclashjelly and performs a powerful blast.
      • 2 Fullbottles:
      • Fullbottle + Sclashjelly:
        • Robot + Robot: Grease covers himself in golden energy and slides at the enemy for a punching maneuver via the Variable Jelly, before surfing around the enemy whilst shooting it multiple times, then performing his Scrap Finish attack.
    • Discharge Crash/Twin Finish (ディスチャージクラッシュ/ツインフィニッシュ Disuchāji Kurasshu/Tsuin Finisshu): With the Twin Breaker in Beam Mode, and the Machine Splash Armory, Grease channels the energy of 2 Fullbottles or a Fullbottle and the Robot Sclashjelly, plus the energy of an inorganic FullBottle in the Sclash Driver, Grease performs a powerful shooting attack.
      • 2 Fullbottles:
        • Kuwagata + Fukurou (in Twin Breaker) + Castle (in Sclash Driver): Grease coats the Twin Breaker in blue and yellow energy mixed together in the shape of the Castle FullBottle logo before ramming into the enemy.
      • Fullbottle + Sclashjelly:

Appearances: Build Episodes 16, 18, Birth! KumaTelevi!! VS Kamen Rider Grease!, 19-26, 29-32




Behind the Scenes


Kazumi Sawatari is portrayed by Kouhei Takeda (武田 航平 Takeda Kōhei), who is more previously well known for his portrayal of Otoya Kurenai in Kamen Rider Kiva. As Kamen Rider Grease, his suit actor is Satoshi Fujita (藤田 慧 Fujita Satoshi).


Following Sento and Ryuga, one of the kanji used to spell his name also represents an animal, Sa (), which poetically means "monkey". It could be referring to grease monkey, an English slang term for mechanics.


Kazumi Sawatari Dogtag
  • Kazumi's dog tag number '907101080' is a Goroawase pun of Otoya Kurenai: 9 ( Ku), 0 ( Re), 7 ( Na), 1 ( I) , 0 ( O) 10 ( To), 8 ( Ya).
  • Unlike the previous third main riders on the series who are evil at first (Kamen Rider Chaser and Kamen Rider Necrom), Kazumi is only rider who received order from above and never being evil from the start, being more neutral in temperment. He is even repulsed by Prime Minister Tajimi's tendency to send unnecessary reinforcements to invade Touto.