Antidermis was a green-black, gaseous substance which formed the life essence of all Makuta. Antidermis appeared as a green and black fog that was part liquid and part gas. All of the Makuta were originally created from a pool of antidermis on an unnamed island, where the antidermis was given solid form and made to comprise their inner organic tissue. This antidermis was protected by an outer suit of protosteel armor. Many thousands of years after their creation, the Makuta naturally evolved to a point where their antidermis tissue reverted to a gaseous state, an event which granted the Makuta new abilities, but also one of their greatest vulnerabilities. On the one hand, they became able to exit their protosteel armor as free-floating clouds of antidermis and take possession of bodies which did not have another spirit inhabiting them. On the other hand, any Makuta who stayed in a free-floating state for a long period of time risked dispersing permanently and dying.
When the Piraka invaded Voya Nui, they constructed a crystal vat inside of their stronghold which they used to allow the free-floating antidermis essence of Makuta Teridax to coalesce. The Piraka did not understand the antidermis's true nature, but instead described it as a "virus." The Piraka used some of Teridax's antidermis as ammunition for their zamor spheres; when these green zamor spheres struck a living target, the target's mind became enslaved to the Piraka's commands. The Piraka used antidermis zamor spheres to take control of the Matoran population of Voya Nui and the Toa Nuva. The effects of antidermis could be reversed by firing a zamor sphere filled with energized protodermis at the affected being, as the antidermis shielded the possessed being from contact with the energized protodermis but was itself destroyed by it. Antidermis zamor spheres had no effect on the Toa Inika, as the electricity coursing through their bodies immediately neutralized it.
Notes
The Great Beings created the original antidermis and gave it its knowledge of Mata Nui's mission. Creating the Makuta was part of Mata Nui's programming.1
Antidermis happened to take the form of a gaseous-liquid mix.2
Antidermis was greenish-black in color.3
Makuta energy likely couldn't be destroyed, but without a body or some other kind of enclosure it would dissipate over time to the point that the Makuta's consciousness would cease to exist, effectively resulting in the Makuta's death.4
Makuta armor contained their energy. Without the armor, the energy dispersed; this is what antidermis was.5
Makuta could be conscious in antidermis form.6
In antidermis form, a Makuta could use any mind-based power, such as mind reading, (limited) shapeshifting, illusion, fear, anger, and confusion.7
The Piraka named Teridax's energy "antidermis".8, 9
Antidermis couldn't possess beings with spirits, but it could infect them in the same way as infected Kanohi were used.10
Antidermis was certainly a component of kraata, but they were unlikely to simply be solid antidermis.11
Makuta kept their antidermis forms intact with willpower.12
Antidermis could probably change color and opacity.13
It'd make sense for liquid antidermis to be able to change density and viscosity.14
Properties as a Virus
Antidermis was the name which the Piraka gave to the green-black virus they used to enslave the Matoran of Voya Nui. In fact, this "virus" was actually the life essence of Makuta Teridax. Axonn shattered the Piraka's antidermis vat, forcing Makuta to find another host body or risk being permanently dispersed into the atmosphere.15
The Piraka's zamor spheres contained the antidermis virus, which could enslave others.16
Antidermis infections appeared to make the Matoran of Voya Nui obey Piraka commands. This would not have worked for the Toa Inika.17
Energized protodermis could counteract the effects of an antidermis infection.18
Energized protodermis destroyed antidermis without harming the infected being because the virus overlaying the Matoran was not destined to transform.19
Antidermis overlaid an infected Matoran, so the first thing energized protodermis delivered via Zamor sphere would come into contact with would be the virus.20
An antidermis infection would make a being obey whoever infected them, the effect was not specific to the Piraka.21
Teridax could not seize control over the Voya Nui Matoran his antidermis was used to infect. Infected Matoran obeyed anyone's orders, not just Teridax's.22
Beings infected by antidermis obeyed anyone who gave them orders, even if the one giving orders was opposed to the one who initially infected them.23
A second exposure to antidermis would likely have no effect on someone already infected.24
If a Matoran directly exposed themselves to antidermis, they would stand around waiting for orders.25
If a Matoran was accidentally exposed to antidermis, they would stand around waiting for orders.26
Antidermis couldn't enslave Brutaka's species.27
The effect of antidermis and the effect of infected masks were similar in strength.28
Antidermis could not be recollected from a target it had infected.29
The Piraka were just as susceptible to the effects of antidermis as the Matoran were.30 The Barraki were equally susceptible.31
Antidermis enslaved every species except for Brutaka and the Toa Inika.32