Glistening oil
Glistening oil, also known as Phyrexian oil or simply Ichor (EYE-ker), is a viral substance engineered by the Phyrexians to spread corruption wherever it is transported to.
Glistening oil, also known as Phyrexian oil or simply Ichor (EYE-ker), is a viral substance engineered by the Phyrexians to spread corruption wherever it is transported to. It is both a contagion and a mutagen, used to compleat creatures into Phyrexians, as well as power Phyrexian machines. After the death of Elesh Norn, the altered oil from New Phyrexia was rendered inert and harmless.
Description
Glistening Oil is composed of two main elements: oil and powerstone nanites. It is normally black, but can also be of other colors like purple, green and gold. These components can be forced apart under specific sound frequencies, something Urza, Xantcha and Ratepe exploited; Ral Zarek later rediscovered this method. In New Phyrexia, the oil was further mixed with other fluids such as the liquid metal of the Quicksilver Sea and the necrogen gas of the dross swamps, so in art in Phyrexia: All Will Be One it is sometimes depicted as silver or green.
The oil imparts a genetic memory of Yawgmoth, Phyrexia, and the Phyrexian language, creating a throughline for the Phyrexian culture.
The nanites in the oil have an adverse reaction with the angelic form. Halo is known to protect against phyresis and damages Phyrexians. Innistrad skaab-stitching and Phyrexian zombification were found to be mutually exclusive processes, as stitching involves the use of angel blood. Curiously, it was still possible to compleat angels, possibly due to the mycosynth of Mirrodin.
History
On Phyrexia
Oil was present on the plane that would become Phyrexia when Dyfed brought Yawgmoth there. Given that Phyrexia as a concept and civilization was Yawgmoth's creation, and Dyfed claimed that the metal creatures of the world could be consumed, it seems likely this oil was once innocuous but later modified into a corruptive agent. Indeed, once Yawgmoth's will became one with Phyrexia, the oil began exhibiting mutagenic properties it previously did not have. Still, the oil was not refined as a fully infectious agent by the time of the first Phyrexian invasion of Dominaria, though the new infectious variant did make it to Mirrodin.
The Fifth Sphere of Phyrexia, called the Boiling Sea, was an ocean of glistening oil used by Vat Priests of the Fourth Sphere to breed newts.
On Dominaria
In post-apocalyptic Dominaria, black-aligned knights and wizards were tainted by the lands where Yawgmoth and his minions had been defeated. Evidence of this corruption existed in the black ichor that ran from their eyes. In the Mending Era, a sample of live glistening oil recovered from Koilos was rumored to be preserved in the labs of the Academy of Tolaria West.
The Infection of Karn
Without knowing it, Karn carried a trace of the Phyrexian oil within him, inside the Phyrexian heartstone granted to him long ago by Urza. Karn left traces of the oil in his travels from plane to plane, including the artificial world that he created: Mirrodin.
The Infection of Mirrodin
The glistening oil planted a virus on Mirrodin that slowly spread. The first to be infected was Mirrodin's keeper, Memnarch. Unbeknownst to most Mirrans, Phyrexia was rebuilding itself, using their world as its host substrate. Mirrodin's metal structures and metal-infused inhabitants were a perfect breeding ground for the spread of Phyrexian corruption. As the nascent civilization of Phyrexia expanded in secret, it struggled to evolve a unified purpose, and the danger to the plane of Mirrodin grew until it evolved into New Phyrexia.
The glistening oil was the catalyst for the evolution of mycosynth and was found in large quantities in the corrupted Quicksilver Sea. Kraynox, the Deep Thane, created a layer of glistening oil below Mirrodin's surface known as the Fourth Sphere (in addition to the Surface, Core, and Furnace). This layer was later taken over by the praetor Jin-Gitaxias, who drained the Quicksilver Sea above into it, creating a massive reservoir of glistening oil.
Jin-Gitaxias and his faction used the vedalken's blinkmoth serum to enhance the glistening oil, making it more virulent and able to proliferate through organic material at record speeds. The praetor also discovered how to compleat planeswalkers with the oil through research on Kamigawa's kami spirits and experimentation with the Reality Chip. These enhancements made the oil harder for other mortals to resist, weakening Melira's healing abilities.
However, Norn had also altered the oil to allow only herself to transmit new orders. As New Phyrexia phased out of existence, glistening oil all across the Multiverse was cut off from its source and rendered inert. Some Phyrexians stopped in place, while others crumbled apart. Those already compleated fell to the ground as if in a deep slumber. Though some beings recovered from compleation, most died.
It is unknown if the glistening oil left in the Multiverse through other means, like Karns' planeswalks, was also rendered inert, as Jin-Gitaxias did not enhance this oil.