Shadow Virus

The Shadow Virus was an element-tainting Makuta Virus created by Makuta Mutran.

Creation
The Shadow Virus was created by Makuta Mutran when he funneled the power of the Karda Nui Energy Storm into a Tridax Pod. It is unknown how he managed to do this, but when the Shadow Leeches came into contact with the almost limitless power of the Storm, they were vaporized, leaving behind a gaseous, semi-sentient creature that held all of the powers contained in the Leeches, but to a larger scale. When Mutran mixed the creature with several other Makuta Viruses, it became a vapor that corrupted any element it came in contact with, blending it with Shadow, and allowing any being with control over Shadow to control the element in question.

Powers and Effect
Whenever the Shadow Virus encounters any of the fundamental elements (Ice, Water, Earth) the element is mixed with Shadow, allowing Shadow-controlling beings such as Makuta or Shadow Toa to control the element. The Shadow Virus also taints the nature of Matoran and Toa who come in contact with it, leaving them either depressed or prone to uncontrolable rages. Matoran and Toa with a strong will, however, can overcome the Virus's effect and recover.