Kazumi Sawatari

Kazumi Sawatari (猿渡 一海) is Kamen Rider Grease (仮面ライダーグリス), who hails from Hokuto and is the leader of the Hokuto Three Crows.

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. When Kazumi's resources were depleted, he willingly enlisted himself to be a test subject for Faust to futher insure his workers' survival. As a side effect of the experiments, Kazumi lost his memories, though it was later hinted that he continued to retain them, just that he chose not to remember.

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.

Hokuto-Touto War
Kamen Rider Grease stole the Phoenix and Robot Fullbottles from Sento.

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.

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.

Personality
Kazumi's demeanor alternates between calm and composed to maniacal and ruthless, 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.

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 did not blame Sento, he still resolved to have a fair fight with the latter that would be held in the proxy war between Touto and Hokuto.

Powers and Abilities

 * 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.

Weaknesses

 * Mii-Tan: Since Kazumi is a huge fan of Mii-tan, he quickly loses his fighting will 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.

Forms
Grease "Tsubureru! Nagareru! Afurederu! Robot In Grease! Buraa!"

- Transformation announcement

Rider Statistics Ability Perimeters: Grease's base form is accessed by inserting the Robot Sclashjelly into the Sclash Driver and pumping the lever.
 * Rider Height: 203.0 cm
 * Rider Weight: 118.3 kg
 * 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.

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):
 * Rider Kick: Grease uses his Machine Pack Shoulder (マシンパックショルダー) to generate Variable Jelly (ヴァリアブルゼリー) 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) 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 Machine Splash Armory as they explode upon latching to his targets.
 * Discharge Crash (ディスチャージクラッシュ): 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 the Batrotor Blade, 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): Grease channels the energy of a Fullbottle or the Robot Sclashjelly and performs a powerful blast.
 * Fullbottle:
 * Sclashjelly:
 * Robot: Grease shoots the enemy with gold lightning in rapid succession.
 * Twin Finish (ツインフィニッシュ): 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 -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): Grease channels the energy of a Fullbottle or the Robot Sclashjelly and performs a powerful slash.
 * Fullbottle:
 * Sclashjelly:
 * Twin Break (ツインブレイク): Grease channels the energy of 2 Fullbottles or a Fullbottle and the Robot Sclashjelly and performs a powerful slash.
 * 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, causing his transformation to cancel.
 * Scrap Finish/Twin Break (スクラップフィニッシュ/ツインブレイク): 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 slash.
 * 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.

Appearances: Build Episodes 16,, Birth! KumaTelevi!! VS Kamen Rider Grease!, Build 18-23

Devices

 * Sclash Driver - Transformation device.
 * Sclashjellies - Transformation trinkets.
 * Fullbottles

Weapons

 * Twin Breaker

Portrayal
Kazumi Sawatari is portrayed by Kouhei Takeda (武田 航平), 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).

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