Shadow Leech
Mutated Kraata designed to drain light and corruption. Created by Mutran and allies, they transformed dozens of Matoran before the Energy Storm wiped them out.

What slipped past the Av-MatoranAv-MatoranThe Light-element Matoran, prototypes of their species, who colonised Karda Nui from the Southern Continent and built the Stalactite Villages above the Swamp of Secrets. was a slime-covered leech about two feet long, faintly glowing with a pale, sickly light, per BIONICLEBIONICLE: Matoran AdventuresA 2002 GBA platformer where you play as one of six Matoran fighting Bohrok across Mata Nui's islands. Legends 9: Shadows in the Sky. That creature was a Shadow Leech, a weapon engineered by MutranMutranMutran is a Makuta of the Brotherhood of Makuta who serves as the Makuta of Voya Nui and is among the most prolific Rahi creators within the organization. Hailing from the Southern Islands, he wears the Great Shelek and commands the powers of Shadow and Silence alongside the full range of Kraata abilities, wielding a Shadow Blade, Shadow Spear, and Tridax Pod in combat., TridaxTridaxMost Makuta wanted the Plan to succeed. Tridax wanted what came after, and he was building a private army of stolen Toa of Light in a Destral basement to make sure he got it., and ChiroxChiroxA Makuta of the Brotherhood who questioned Teridax's plans before being sent to Karda Nui. to transform living beings into shadow-corrupted versions of themselves. The MakutaMakuta (Species)Shadowy Antidermis beings and the Brotherhood's elite, Makuta commanded darkness and shaped the Matoran Universe's fate. had created a mutated KraataKraataSlug-like creatures birthed from Makuta's essence, designed as both weapons and the cores of Rahkshi armor. capable of draining both elemental power and moral alignment in a single attack. It was corruption as biology.
Creation and Function#
MutranMutranMutran is a Makuta of the Brotherhood of Makuta who serves as the Makuta of Voya Nui and is among the most prolific Rahi creators within the organization. Hailing from the Southern Islands, he wears the Great Shelek and commands the powers of Shadow and Silence alongside the full range of Kraata abilities, wielding a Shadow Blade, Shadow Spear, and Tridax Pod in combat.'s work in biological corruption reached its peak with the shadow leech. In The MutranMutranMutran is a Makuta of the Brotherhood of Makuta who serves as the Makuta of Voya Nui and is among the most prolific Rahi creators within the organization. Hailing from the Southern Islands, he wears the Great Shelek and commands the powers of Shadow and Silence alongside the full range of Kraata abilities, wielding a Shadow Blade, Shadow Spear, and Tridax Pod in combat. Chronicles, the MakutaMakuta (Species)Shadowy Antidermis beings and the Brotherhood's elite, Makuta commanded darkness and shaped the Matoran Universe's fate. proudly described his creation as "a mutated kraata that could drain the light out of any living being." Working alongside TridaxTridaxMost Makuta wanted the Plan to succeed. Tridax wanted what came after, and he was building a private army of stolen Toa of Light in a Destral basement to make sure he got it. and ChiroxChiroxA Makuta of the Brotherhood who questioned Teridax's plans before being sent to Karda Nui., MutranMutranMutran is a Makuta of the Brotherhood of Makuta who serves as the Makuta of Voya Nui and is among the most prolific Rahi creators within the organization. Hailing from the Southern Islands, he wears the Great Shelek and commands the powers of Shadow and Silence alongside the full range of Kraata abilities, wielding a Shadow Blade, Shadow Spear, and Tridax Pod in combat. had achieved a weapon that didn't simply kill or injure, but transformed. The creatures were the embodiment of a specific kind of evil. They didn't destroy light. They inverted it.
The shadow leeches inhabited specially maintained hives in Karda NuiKarda NuiThe vast inner cavern at the core of the Matoran Universe, original home of the Av-Matoran, site of the Codrex and the final battle that decided the fate of Mata Nui., ready to spread through the MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. settlements below. Their targeting was indiscriminate. Any living being could become a vector for infection, though MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. proved the most vulnerable to complete transformation.
Victims and Recovery#
A single Shadow Leech attack could wholly transform a MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body.. The infection would strip away their original elemental nature and replace it entirely with shadow affinity. Multiple MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. fell to the infestation in 2008, including GavlaGavlaAn Av-Matoran of Karda Nui transformed into a Shadow Matoran, Gavla led Vamprah's corrupted villagers and resisted restoration. and Kirop among others. Even TakanuvaTakanuvaHidden among the Ta-Matoran as Takua, the disguised Av-Matoran who became Takanuva was the sole Toa of Light produced in the Matoran Universe's full history., the Toa of LightToa of LightThe sole Toa wielding the Element of Light through the Avohkii mask, singular and feared by Makuta itself., was caught and partially drained during his investigations into the plague. The victims remained trapped in their corrupted state indefinitely. Only one remedy existed: a Klakk's sonic scream. That creature's cry could reverse the transformation and restore victims to their original form.
Eradication#
The shadow leech population didn't fade. It ended violently. When the Energy Storm swept through Karda NuiKarda NuiThe vast inner cavern at the core of the Matoran Universe, original home of the Av-Matoran, site of the Codrex and the final battle that decided the fate of Mata Nui., it annihilated the entire hive. MutranMutranMutran is a Makuta of the Brotherhood of Makuta who serves as the Makuta of Voya Nui and is among the most prolific Rahi creators within the organization. Hailing from the Southern Islands, he wears the Great Shelek and commands the powers of Shadow and Silence alongside the full range of Kraata abilities, wielding a Shadow Blade, Shadow Spear, and Tridax Pod in combat.'s carefully maintained breeding operations and experiments were destroyed alongside his creatures. The infected MatoranMatoranThe most abundant species in the Matoran Universe, chosen by Mata Nui to inhabit and maintain his cosmic body. who survived the storm were left to either find a Klakk's cry or remain transformed.
Compiled from primary sources by Lore Fortress editorial. Reviewed by Joe Garratt, Editor-in-Chief.
Sources
- WikiBS01 Wiki - Shadow Leech — Comprehensive entry on Shadow Leech physiology and role in 2008 storyline
- SerialThe Mutran Chronicles — Mutran's firsthand account of shadow leech development and use
- BookBIONICLE Legends 9 - Shadows in the Sky — First appearance and Shadow Leech swarms in Karda Nui
- BookBIONICLE Legends 11 - The Final Battle — Shadow Leech infection effects and Klakk cure
- SerialDestiny War — Chirox and the shadow leech creation experiments
Spotted a factual error or a primary source we missed? Email a correction. Every flagged claim gets reviewed.
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