Nefandi (Left-Handed Legacy of the Abyss)
It is uncertain if it began as a Moros or Mastigos Legacy, but it is certain that the Nefandi can corrupt a willing member of any Path to their cause. It is rumored that the Silver Ladder may secretly train Nefandi, for their unparalleled mastery of the Abyss - a neccesary evil, if the Abyss is to be overcome and a new Celestial Ladder built. If such were revealed to be true, it could destroy the Order.
Nefandi learn the Abyss Arcanum as their Ruling Arcanum, losing their previous Ruling Arcana and Inferior Arcanum. All other Arcana become Common to them. They may teach the Abyssal Arcanum to other Mages, who learn it as if it were an Inferior Arcanum. Many spirits of the Abyss (such as Acamoth) may also teach the Abyssal Arcanum as well, to a greater or lesser degree.
First Attainment: Requires Gnosis 3, Abyss 2 - Activate or deactivate "Eyes of Sleep" as a reflexive action. It lasts for as long as the Nefandus wills it to.
Second Attainment: Requires Gnosis 5, Abyss 3 - Activate "Sail the Starless Ocean" as an instant action by spending 1 Mana and rolling Composure + Occult + Abyss. May be activated as a Reflexive action by spending a Willpower point as well.
Third Attainment: Requires Gnosis 7, Abyss 4 - Activate "Consume the Fallen World" for 1 Mana. It lasts a number of turns equal to your Gnosis.
Suggested Oblations: Engaging in your Vice, spending 4 hours contemplating a black sky, making a Morality check, causing another to make a Morality check
The Abyss as an Arcanum
Purview: Disbelief, Quiessence, Paradox, Abyssal spirits, traveling to and from the Abyss, smothering magic, destroying spirituality. To a lesser degree, darkness, vice, corruption and failure.
This is the Arcanum that is forbidden, the Ars Abyssal, the mysteries of the blackness that seperates the Fallen World from the Supernal. It is the art of Paradox, the mastery of Quiescence, the death of Magic - but also the freedom from the lead weight of the chains that bind Mages to the Fallen World, a way to reach out and beyond to the Supernal with an ease that is difficult to imagine. It is corruption, but with the promise of salvation, if one is strong and sure. Few mages have the moral fiber to daily look into the Abyss, the Abyss looking back - fewer have the strength to win the blinking contest with the unblinking monsters that lurk therein.
Any mage may learn the Abyssal Arcanum as an Inferior Arcanum with the aid of a teacher, such as a Nefandus or certain Abyssal spirits, akin to the Acamoth. The Nefandi may learn it as their Ruling Arcanum.
A mage who studies Abyssal lore has their maximum Wisdom capped at (10 - Abyssal Arcanum). So, a Mage that is an Adept of the Abyss may not have a Wisdom greater than 6. Such is the price paid for learning truths man was not meant to know.