"You made it this far. I'm impressed! You interested in a real challenge?"
―Split Mushroom, Mega Man X4

Split Mushroom (スプリット・マシュラーム) is a troublemaking mushroom-based Reploid in Mega Man X4. He was once the administrator of a Bio Laboratory, but when the lab was shut down, he was decommissioned. Mushroom was later resurrected by Sigma as a Maverick during the Repliforce War so he could aid Repliforce's coup by reactivating and fortifying the Bio Laboratory, attacking whoever entered there for fun. Split Mushroom has a cruel and playful nature, being like a child, and sees the destruction of intruders as the best game of all.[1]

When X finds him, Mushroom says that he received orders to terminate X ("play" with him in the Japanese version) if he appeared. With Zero, Mushroom is impressed that he managed to reach him, and challenges him to test his strength.

Power and abilities

Split Mushroom can release poison gas and copies of himself, and is able to jump very high, performing somersault rolling attacks.

  • "Clone Attack" (分身攻撃) - Mushroom jumps to a wall and releases six energy copies.
  • "Clone Attack 2" (分身攻撃2) - Mushroom jumps to the center of the room and creates a more realistic copy that will imitate him. Both will run from one corner of the room to the other, then jump back to the corner. After some time they will attack by jumping and hitting the ground with their heads, releasing poison gas. The real Split Mushroom is faster than the copy.


Split Mushroom is very quick and agile, performing acrobatic jumps and bouncing from wall to wall. He also, as his name implies, has the ability to clone himself. He will usually start the battle out by clinging midway up a wall and releasing six energy clones; these can canceled out with an electrical attack or by just attacking Split Mushroom himself with his weakness. Also on occasion he'll jump high and release damaging powder, which can be avoided by clinging to a wall as high as possible. When his health is down to half, he'll create an exact clone of himself and the two will proceed to run throughout the room, rebound jumping of the walls. The only way to cancel this is to strike the real Split Mushroom with his weakness, Lightning Web (as X) or Raijingeki (as Zero). Otherwise, be prepared to follow their routine, pulling off some fancy dodging maneuvers.

It is recommended that the player face Split Mushroom when they have a more sizeable life gauge if not in possession of his weaknesses, the reason for this and as stated above, Mushroom will duplicate himself causing a two vs one situation. However, what makes this battle difficult is the fact that both Mushroom and the clone move at different speed, easily causing confusion and mistiming on the player's action.

Most bosses show the ability gained by the player during the fight. X's Soul Body is reminiscent of Split Mushroom creating image clones of himself. Zero's Kuuenbu and Kuuenzan is reference to Split Mushroom's acrobatic spin jumping.


In-battle quotes

  • Note: These are only in the original Japanese version of the game.
Hayaku asobou yo! Hurry up, let's play! Pre-battle line
Hīrō-gokko shiyou, kimi warumono ne! Let's play "heroes"! You're the villain! Pre-battle line
Yowai tomodachi wa iranaikara ne. I don't need weak friends. Pre-battle line
Ike! Go! When creating clones of himself

When playing as X

Split Mushroom: Are you X? I'm under orders to terminate you.

X: What?! Who's orders?

Split Mushroom: Take a wild guess.

When playing as Zero

Split Mushroom: You made it this far. I'm impressed! You interested in a real challenge?

Zero: Who's your commanding officer?

Split Mushroom: Never mind that, it's time to fight!

Other appearances

Split Mushroom is fought alongside Infinity Mijinion in the X Challenge from Mega Man X Legacy Collection.

Other media

Rockman X4 manga

When X finds Split Mushroom, he realizes that Mushroom is malfunctioning and tries to stop the Maverick without destroying him so he can be repaired, remembering that something similar happened with Wire Sponge. He is successful, but Double appears and takes the unconscious Split Mushroom from him, slashing him into bits multiple times in front of X until nothing remained.

Archie Comics

Split Mushroom has a cameo appearance in Mega Man #35 where he was listening to Dr. Cain's conference with the Arcadia Council. He would later appear in Worlds Unite as a member of Sigma's Maverick Army, created to aid in his master's plans of conquest.



  • Split Mushroom's attack pattern is similar to that of Gemini Man's from Mega Man 3, as they both create clones of themselves that run back and forth. However, Split Mushroom's clone does not react to X's movements like Gemini Man's does to Mega Man's.
  • Split Mushroom is the only boss in the series to be based on an organism of the Kingdom Fungi.
  • Split Mushroom is one of three Mavericks in Mega Man X4 to be affiliated with Sigma, having Sigma's insignia instead of Repliforce's; the other two being Cyber Peacock and Magma Dragoon.
  • There's a grammatical mistake in the dialog between Split Mushroom and X. X says, "What!? Who's orders?", when it should be, "What!? Whose orders?"
  • Split Mushroom is the first Maverick to be voiced by a female Japanese voice actress, and the only one of the eight bosses to have a female voice actor in Mega Man X4
  • When X faces him, Mushroom says he was told to play with him by his mysterious superior, insisting that X "get[s] to play the bad guy". It serves as a metaphor for the game's plot; both sides of the Repliforce conflict claim to be heroes attacking villains when it is a sham encouraged by a third party.
  • Depending on where the player is standing when Split Mushroom enters the field, they can be damaged by his spore emission just before the dialog exchange occurs. 
  • In the prototype version of Mega Man X5, a pink silhouette of Split Mushroom can be fought in Spike Rosered's stage; this can only be accessed through the use of a GameShark code.[2]
  • Split Mushroom's body shape, playful attitude, odd organism choice, malfunctioning premise, and nickname all draw parallels to Wire Sponge.
  • Split Mushroom is the only boss who isn't renamed from the Japanese version of X4. "Mushroom" is generally pronounced as "masshurūmu" in Japan, but he is pronounced as "mashurāmu" in the Japanese version.

See also


  1. Split Mushroom's profiles from the Rockman X4 official site, Rockman Memories, and Mega Man X Legacy Collection
  2. Rockman X5/Megaman X5 Prototype Unused Stages

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