The Keepers explorations into the limits of the void from which they draw their power have resulted in an entirely separate realm of occult belief. Investigating the Abyss as a tangible concept, rather than some abstract reference, Abyssal Occultists attempt to gain knowledge of the true nature, and thus the true power, of the shadow realms just beyond our sight.

Note: Abyssal Occultism is a fairly obscure knowledge. Only those Lasombra that really take the time and put the effort into exploring the nature and limits of their Obtenebration abilities should possess this knowledge. As a good standard, Lasombra should first have at least an Occult ability rating of 3, and an Obtenebration rating of 3, before they can begin learning Abyssal Occultism. A good way to measure how much Occultism your character would be able to learn is by how far they've mastered Obtenebration. The most ideal scale would go something like this (with Occult 3 as a prerequisite):

Obtenebration 3: Able to learn the first dot in Abyssal Occultism
Obtenebration 4: A second dot
Obtenebration 5: A third dot.

The fourth and fifth levels of this ability, however, should only come through either further mastery of the Obtenebration discipline or (ideally) the character questing for an Elder that will teach them more about the true nature of the Abyss. Overall though, Storytellers should make the characters really work for attainment of this knowledge, as it is such an obscure offshoot of the standard Lasombra traditions.

You know that the darkness you control is something "other" than mere shadows.

You have an understanding that the summoned darkness comes from some sort of alternate plane of reality, and that when you summon some shadow construct, it is actually a portion of that reality entering our own.

You know that, despite your apparent ability to "control" it, the Abyss itself has some sort of sentience of its own.

You know of (and might have encountered) the dark spirits that roam the Abyssal dimension, and that it is really lesser aspects of these that are called forth with Obtenebration. However, their true motivations are still a mystery to you.

You believe you understand the true nature of the Abyss and its inhabitants, and your explorations lead you to suspect that some ritual or pact must have once been enacted to bind the Lasombra blood to the dark dimension, though who might have done it, and why, are things still to be discovered.

Ed. Note: While this Knowledge closely resembles the Occult specialization described in Clanbook Lasombra Revised and details almost exactly the same information, the Bloodsisters find this description less ambiguous and easier to use in terms of rolls. As such, we have chosen to publish it despite the similarities. - Benedira