This article is about the character. For the ability, see Beast Out.
"Challenging my unit was both foolish and reckless! You are nothing more than my prey... One that is soon to be retired!"
―Slash Beast, Mega Man X4

Slash Beast, known in Japan as Slash Beastleo (スラッシュ・ビストレオ), is a lion-based Reploid and one of the Maverick bosses in Mega Man X4.


Slash Beast is a tall Reploid with the head and claws of a lion. His armor is a sandy brown, and he has the Repliforce insignia on his shoulder.

Slash Beast shows dauntless courage in battle, fearing no one and loving the tension of a good fight. He appears to care little for status, loyalty, or morality, having joined Repliforce just so he could fight. In the manga, he is especially ruthless and his brave facade fails when he begs for his life in front of X.


Slash Beast is the captain of the Reploid Army who only enlisted in Repliforce to freely exercise his combat abilities. During the Great Repliforce War, Beast was put in charge of guarding Repliforce's military supply train.

Power and abilities

Slash Beast possesses excellent hand-to-hand combat skill with his speed and strength, performing high jumps and claw attacks that pair with his combat skill.

  • Jump Attack - He jumps and attacks, varying the distance and height. Sometimes he will fall straight down to stomp the target.
  • Rush - He charges in the target's direction to attack with his claws.
  • Twin Slasher - He can shoot crescent moon-like shock waves from his somersault/invert front-flip kick moves.
  • Counter-Attack - After losing half of his energy, Slash Beast will sometimes assume a defensive position with his claws growing red. If he is attacked, he will counter with the Twin Slasher.
  • Jump Strike - After losing half of his energy, he will sometimes perform a lunge jump at the player, differing from his regular jump as he is in a forward-striking position. If his lunge connects with the player, he will slam his opponent into the wall.


The battle can be easy or hard depending on what character is being played. As X, the Ground Hunter is the best choice. The first hit will break his claws off, disabling his Twin Slasher attack, and any additional strike will cancel his attacks, trapping him in a loop. Zero has his work cut out for him, as he'll need to keep moving to avoid the charges, slashes, and (when his health is low enough) avoid getting grabbed and shaken like a ragdoll. Zero can hit him with Raijingeki if there is a clear shot. Also, if Zero has his Tenkuuha ability, he can neutralize Slash Beast's Twin Slasher.

Most bosses show the ability the player will gain during the battle. For X, his Twin Slasher is identical to the crescent energy generated by Slash Beast's somersault kick. For Zero, his Shippuuga comes from Slash Beast's charge attack when at low health.


When playing as X

Slash Beast: Challenging my unit was both foolish and reckless! You are nothing more than my prey... One that is soon to be retired!

When playing as Zero

Slash Beast: You dared to attack my unit?! I'm gonna enjoy fighting you!

Battle quotes

  • Note: These are only present in the original Japanese version of the game.
Line Translation Usage
Kozō! Chitto wa tanoshima sete kureru ndarou na! Hey brat! You’ll give me a bit of fun, won’t ya! Pre-battle line
Chō tokkyū de anoyo ni okutte yaru! I'll send you to Hell on the Super Express! Pre-battle line
Ureshī ze! Hisashiburi no tatakaida! I'm so happy! My first fight in a while! Pre-battle line

Other appearances

Slash Beast is fought alongside Crescent Grizzly in the X Challenge from Mega Man X Legacy Collection.

Other media

Archie Comics

Slash Beast appeared in the Worlds Unite crossover event, in which he and his fellow Mavericks were revived by Sigma and fought against the unified heroes assembled by X, Sonic the Hedgehog, and Mega Man.

Rockman X Giga Mission

X8NavigatorAlertIconEdit.png This section requires expansion.

He was revived by the Extreme, becoming more powerful, but is defeated by X.

Rockman X4 (manga)

Slash Beast's futile charge against Ultimate Armor X, which costs the former his life.

Slash Beast appears in the manga version of X4 as a member of the Repliforce, just as he was in the game. Prior to the coup d'etat, he is seen in a flashback assisting Zero on a mission to stop a dangerous volcanic eruption.

Beast leads his Repliforce freight train on a rampage throughout a city, destroying a smaller train in its path along with some buildings and structures. After Iris is critically injured and in a stasis pod because of Cyber Peacock's self-destruct causing computer terminals to blow up near her, the only way for her to be saved is with a special vaccine. The vaccine chip is in Beast's possession on the train, so Zero attacks it and kills several of Beast's underlings along the way.

Beast is very ruthless in the manga with little care for his underlings. When one of his subordinates tells Beast that one of their Repliforce trains had been destroyed by Zero's attacks, he ruthlessly murders the soldier by slicing him apart and then angrily shouts the soldier stained the Repliforce flag with his failure. Zero continues his mission to reach Beast and the vaccine, but X confronts him first wearing the Ultimate Armor that he got from Dr. Light's capsule. Beast confidently replies that he considers X to be nothing more than prey, and that he'll have fun killing him. He lunges at X, who then effortlessly kills him with his Buster. The power from X's attacks leaves Beast's entire body been blown to smithereens apart from his right hand which is holding the vaccine in its palm. X says Beast begged for his life before he killed him, which X found ironic since he had so casually murdered one of his Repliforce subordinates moments earlier.



  • Slash Beast may be a tribute to Guile and Charlie from the Street Fighter series (like Magma Dragoon is to Ryu, Ken and Akuma). Like them, he is military and his somersault attack is similar to their "Flash/Somersault Kick" special move.
  • Oddly, Slash Beast's artwork shows him as orange and yellow, although, in-game, he is brown with yellow highlights.
  • Slash Beast is one of two Mavericks in the Mega Man X series to have two separate battle entrances. In the first encounter, he uses his speed to outrun the train and jumps on it. The second encounter, on the other hand, is just him inexplicably falling from the top of the screen, simply due to the fact that there is no train on the Final Weapon. The other character to have this trait is Dark Mantis, if certain conditions are met in his stage.

See also

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