It takes too much effort to save debilitated
Reploids, so you just kill them instead!
That's what Maverick Hunters do?
— Nitrous Marcidus, Disturbances
Nitrous Marcidus
Nitrous Marcidus as he appears
in Mega Man X: Unit 49.
Comic Information
First Appearance Disturbances
Personal Information
Birthplace: Jamison Liquid Metal Engineering Facility
Species: Liquid Metal Reploid
Gender: Male
Status Alive
Creator: Jamison LMEF Researchers
Combat Information
Primary Weapons: Liquid Metal
Secondary Weapons: Blob Buster
Affiliations and Positions
Affiliations: Neo Maverick Army
Position: Warmonger
Allies: Saturn

Nitrous Marcidus's sprite.

Nitrous Marcidus is an antagonist introduced in Mega Man X: Unit 49's second season. He is a Liquid Metal Reploid developed by the Jamison Industries who rebelled and lives to retribute the pain he suffered to all mankind.


Nitrous Marcidus was very traumatized by the days in which he was an experiment of the Jamison LMEF Researchers, and the memories of the torture suffered by him and his brothers are rooted in his memory. His hatred towards his cynical creators made him hate mankind as a whole, devoting his life to make humans pay for all the suffering caused to Reploids who have lived in similar conditions, and to free those who are still trapped.

Marcidus became obsessed with "experiments" that are actually ingenious ways of torturing his victims to death. Whenever questioned about his means of bringing justice, he justifies with the actions of his own creators. If he is a criminal, then they must have been as well and Reploids cannot be treated like he was.

Marcidus found shelter in Saturn, whose ideal was aligned with his will of vengeance and sheltered him as a father. 


Just like all the Liquid Metal Reploids of the Jamison Industries, Nitrous Marcidus' body is made of a substance that can shift between solid and liquid in their own will, which corrodes the parts of normal Reploids when it touches them while heated or liquefied. Due to that, his shapeshifting abilities can be nullified if he is frozen by an ice weapon. His body can regenerate as long as there is liquid metal for him to feed on, since the only part that can be truly damage is his "brain", a solid nucleus that contains his mind and maintains the liquid metal under his control. However, it seems there is a limit for how much he can grow in size, since even with a giant deposit on his favor his attacks were still limited. Marcidus' shapeshifting abilities are also limited, meaning he can only choose between a short set of shapes and sizes. Despite his limitations, Marcidus has the unique ability of splitting his own nucleus into two smaller copies, although that shrinks his maximum size.

Marcidus can morph his arm into Blob Busters that expel charges of liquid metal in very high speeds, and his back has a shield that deflects buster attacks.

When immersed, Marcidus can use the liquid metal supply to create eruptions or generate giant floating bubbles that can shoot many other pellets before dismantling. Due to that same ability, Marcidus can also launch himself from the liquid metal to a considerable height.

Marcidus can morph himself into a giant ball of liquid metal that displays his monstrous face, being able to shoot more charges of liquid metal. When he has extra amounts of liquid metal available, he can make a succession of movements that consist in forming a bubble and expelling himself until he manages to get his target.


Recommended Reading: Jamison LMEF's History


Marcidus' duplicate makes his last attempt to defeat the Maverick Hunters.

After Nitrous Marcidus was freed by his sister Corrosive Nagaxid from the Jamison LMEF Researchers, Marcidus rebelled in anger and tortured his creators, proposing an "experiment" that consisted in making them swim in a pool of liquid metal. Obviously, all of them were killed in the process. Marcidus became delighted by Saturn's ideals and considered him to be a father. He remained in the laboratories of the Jamison Industries taking care of his brothers who were in an irreversible process of decay. When the Maverick Hunters arrived, he scorned them for killing his brothers instead of trying to help them, since they were screaming for help, so Marcidus challenged them to survive his "experiment" and observed their abilities. As soon as he realized he could not defeat his enemies, he duplicated his own nucleus and let his copy fight them to death while watching the fight from far away. Although part of him died, he considered the experiment to be a success.
Mega Man X: Unit 49 Characters
Maverick Hunters

XZeroAxlSignasAliaLayerPalletteCaptain ElikaNoraPlatinaEncoreBlue KnightRed ThunderFalsettoYingIllusionTricksterRaikaRondineRubre

Earth's Government

Alain • Ardashir • Konrad • Raul • Takahiro • Zhengsheng • Raffould • Millions • Galdwin • Manfred • Prabhu • Seymour


SigmaLumineThe DealerSewer JailratCave BigratThe RatsMaestroDikho & Scatho

Neo Maverick Army

SaturnMysterious ManKranBaronelKerbekerosGigantexShadDoppelgangerDuelistNitrous MarcidusCyrenoxCorrosive NagaxidChaotic GargaleSwift KageckoSnowhunt CoyoteCyclobbering OnimmerDevouriang ShiroidStriking CougaroidThugsOthers


Dr. Henry SnacmanDr. SeigenList of RaDoRB CharactersThe EngineersAkira