Nereium Koopa
Nereium Koopa
Nereium Koopa
Full Name Nereium Koopa
Current Age 11
Gender Male
Species Koopaling
Align Evil
Current Status Alive
Vulnerable To The Following;
  • Jumped On
  • Fireballs
  • Iceballs
  • Tanooki Swipe
  • Cat Attacks
  • Spin Attacks
  • Metallic Flower Attacks
  • Music Note Dash
  • Boomerangs
  • Hammers

Nereium Koopa is one of the Koopalings and is part of a Sub-Group called the Mythical Koopalings. Nereium is the second youngest of this group and is the most easy going of the lot. He has complete dominance over the element of Darkness.


With regards to size, Nereium is the shortest of the seven Mythical Koopalings. He is also the only one that wears clothing other than the wristbands of the other 6. He adorns a Dark Blue Shirt and Blue Pants. His Wristbands appear similar to cuffs as opposed to the traditional version. His hair is Black however the tips are dyed Cyan. His chest plates are very large and shaped like a beak.

His Shell is Black in colour and has shorter and wider spikes than most other Koopalings. He also has a distinguishing feature with his nose due to its shark-like shape he has slightly enhanced smell.


Through the various pieces of lore scattered across all the Mario Games, it is revealed that the Mythical Koopalings existed a long time ago, inidicating and confirming their lack of proper relation to Bowser. The Mythical Koopalings supposedly were from 300 years before the present day in the Mushroom Kingdom and originally helped Bowser's ancestors take over the Mushroom Kingdom and its neighbours until they were eventually sealed away in a Grand Star and Bowser's Ancestors were defeated.

Nereium along with Spiritus were the two leading energy providers for Bowser's Ancestors' army. The duo captured countless power plants and utilized the various electrical enemies of the Kingdoms to their advantages. Nereium and Spiritus despite their age difference were very similar in their ideals, Nereium desired tranquility in darkness and Spiritus desired Energy to create great Thunderstorms.

Prior to their capture, Nereium and Spiritus had commanded a vast dual army, Nereium being the Koopaling of Darkness controlled masses of Boos while Spiritus the Koopaling of Electricity controlled the hordes of Amps which resulted in them easily being able to take over many Power Plants across the Kingdoms which weakened the Kingdoms for the other Mythical Koopalings to finish off. Nereium was the third Mythical Koopaling to be captured, this was due to him being blinded by an attack from several Bulb Yoshis that had formed a squad to take back homelands they had lost during the battles. During this time Nereium was caught off-guard and captured, joining his siblings in an eternal confinement.


Nereium is very calm under most situations and often will resort to flat out ignoring any attempt at combat from enemies. He is easily aggravated however if his hair is messed up or his clothing gets a tear in it. This can cause him to let loose his deadly attacks in a state of absolute rage.


Like most Koopalings, Nereium is able to spin rapidly in his shell to perform dash attacks as well as spit fire. When he shoots fire it will disappear into the ground and appear a little bit after.

Nereium's primary ability is his power over Darkness which allows him to shroud things in absolute darkness causing confusion among his enemies as well as him being able to pull off some tricky tactics.

Game Appearances

New Super Mario Bros. Lambda

Nereium along with the other 7 Mythical Koopalings will appear as Castle Bosses for the 8th to 14th Worlds in the game. Nereium appears as the boss of the 10th World, Buzzy Junction.

During Nereium's Fight he utilizes his surroundings greatly using his dark magic to warp the pipes in the arena to go into random locations, this forces Mario to have to figure out which Pipe goes where and reaching Nereium. In addition Nereium will also summon Fuzzys which move from Pipe to Pipe attempting to hit Mario so the player must be careful.


  • Nereium is one of the only Koopalings to have multiple colours in his hair.
  • His shark-shaped nose is said to be the reason he is able to quickly change from physical to shadow form.
The Koopalings
Canon Koopalings Debuted in 1988 (7) LarryMortonWendyIggyRoyLemmyLudwig Debuted in 2002 (1) Bowser Jr.
Fanon Koopalings Debuted in 2010 (8) HarleyLavoraJacksonRisenTimJacobNoahDeath Debuted in 2012 (9) EllenDragoniaLadyDollyJinkesseTheoPoopbutt Classic (Joke Article)AlexPyotr
Debuted in 2013 (2) MortishaDhuwor Debuted in 2014 (7) PersephoneKrisRossBazyliJustinThomasKevin
Debuted in 2015 (20) AivaPietroIgnisEdwinKoopario (Joke Article)GwendolinePolentamNereiumSirenaeVallatusOrcusSpiritusDracoMulgarthWyvanePattiIagoLammyMoonshineAustin
Debuted in 2016 (23) HarrietRagotonJumpyBro. KoopaPi (Joke Article)Larry 2.0 (Joke Article)DragicaHexagonTroopaAngorTau (Joke Article)IrralNotrom IIO'IdnewIggiYorImmelDullReswob IINotiggy (Joke Article)BroserAbel (Recreation)
Debuted in 2017 (4) DougKlavierNew Poopbutt (Joke Article)Muka Larry