Thunder Slimer (サンダースライマー Sandā Suraimā) is the sub-boss in Spark Mandrill's stage in Mega Man X and Mega Man Xtreme. It is a creature born from an experiment that had "how big can a single cell get?" as subject. It took 10 years for it to grow to its current size, being bigger than X.[1]


Mega Man X

Thunder Slimer resides in the Power Plant and is encased in a huge blob of blue slime that protects it. It releases smaller blue blobs around the room that can glue X to the floor, making him an easy target to Thunder Slimer's attacks. Dashs and charge shots can free X if he becomes glued to the floor.

Under normal circumstances, Thunder Slimer can, in addition to throwing slime and doing a body slam, shoot bolts of electricity. Before using its electric attack, Thunder Slimer must recharge in the center of the ceiling. If Storm Eagle had been defeated before, the Death Rogumer will fall in Spark Mandrill's stage, causing the power plant to lose energy and Thunder Slimer won't be able to recharge, making the battle easier. It is weak to Rolling Shield, and Storm Tornado is also helpful as it can hit multiple times. After Mega Man X defeats Thunder Slimer, it explodes and releases a ton of slime balls out that are harmless to X.

Mega Man Xtreme

Thunder Slimer appears in the digital reproduction from Spark Mandrill's stage. It fights in the same way as the original.

Other appearances

Thunder Slimer appeared as an unit card in TEPPEN.

Hits Data Chart

Amount of shots/hits from weapons it takes to destroy Thunder Slimer.

Mega Man X

X Buster Shotgun Ice Electric Spark Rolling Shield Homing Torpedo Boomerang Cutter Chameleon Sting Storm Tornado Fire Wave Hadouken
1:2:3:4 2:8 2:6 4:4 3:3 2:6 2 1:2 1:2 32


  • For X-Buster, the four damage values are listed according to how long the weapon is charged. The first number is damage done with uncharged shots; the second number is when the weapon is charged slightly (cyan); third number is when the X-Buster is charged even more (yellow); fourth number is when the X-Buster is fully charged (pink).
    • Sometimes, an uncharged shot will inflict two units of damage instead of one, if the enemy has just started moving or if X fires a shot while he is dashing.
  • For the eight Special Weapons, the first number is damage done when the weapon is used in normal fire; the second is when the weapon is used in its charged state.
    • For Chameleon Sting, as the weapon's secondary fire renders X invincible and is incapable of inflicting damage on enemies and bosses, the damage values list only the normal fire of this weapon.
  • For Homing Torpedo, Boomerang Cutter, Storm Tornado and Fire Wave: the secondary fire for these weapons are capable of inflicting multiple hits on a target, so the values listed on the second number is the amount of damage done per hit, not the total amount of damage done.

Other media

Thunder Slimer appeared on the Rockman X manga on a power station controlled by Spark Mandrill. Thunder Slimer is the result of a top-secret experiment that was scrapped due to being considered too dangerous to control. As Spark Mandrill recovered it after it was abandoned, Thunder Slimer became very loyal to him. After being defeated by X, Thunder Slimer used its remaining strength to make part of itself jump on X to attack and protect its master before going offline.

In Irregular Hunter Rockman X, X fought against Thunder Slimer in the area controlled by Spark Mandrill.

Thunder Slimer also appears on the Variant Cover of Mega Man #40 and as part of Sigma's Mechaniloid army in the Archie Comics crossover Worlds Unite.


Similar enemies

Enemies similar to the Thunder Slimer:


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