I've been informed by some more experienced posters on this board that the Vendatores are a closed society, like a Mystery Cult, and that the spell guidelines laid out in the section Apotropaic spells can only be used by those initiated into the secrets of their magic, or who have achieved a breakthrough.
Is this true for their equivalents in other realms, as well?
Does anyone have any good anti-demon spells (beside DEO and CWAD) that can be used without initiation into the restricted guidelines?
I was thinking more of equivalents to things like "Pluck the Billy Goat's Chin"; "Command the Vile Spirit" or "Lash of the Recalcitrant Servant"... spells less focused on simple destruction of a physical body, but which can open up different avenues of attack or defense vs. beings of might, spirits and such unsavouries from each of the different realms.
Sometimes the realms are different.
For example, there is no such thing as Angel's Eternal Oblvion. Coerce the Spirits of the Night is not a mystery spell, but Command the Vile Spirit is.
Would a spell which temporarily strips Faerie Might require a mystery initiation, like I'm told the Infernal version does?
This is clearly false according to RoP:S. The Hermetic Sahirs explicitly also use Apotropaic magic. This doesn't mean you don't have to learn them from someone familiar with them, like how you can obtain Mutantum or Mercurian Spell Mastery options or how you can acquire expansions on Hermetic theory after some breakthroughs. But you don't need to learn them from Venatores.
You don't need a Mystery initiation, though. David agreed with this since he would not allow guidelines requiring Mysteries in the general guidelines pdf on the Atlas site while he did allow the Apotropaic guidelines in.
From my reading of RoP:I the Apotropaic guidelines are available to everyone, although lab texts for the actual spells may not circulate widely. That said, if your troupe decides to restrict the guidelines themselves to a particular mystery group, it's probably both playable and atmospheric. The same would go for faerie and magic equivalents. Divine is problematic; current canon seems to suggest that hermetic magic cannot affect the divine realm but some would argue that the Law of the Divine only refers to God and that creatures such as angels with finite Divine Might can be affected.
Well, if they were part of normal spell guidelines, anyone could invent them without research.
That's the difference between mastery types and spell guidelines.
Anything that is part of normal spell guidelines can be invented by anyone, with no further instruction.
Spell masteries are specific, different abilities not part of the normal arts and spell guidelines; they are hermetic/supernatural abilities. Those must the taught or researched, whatever their sources.
The only spells I've seen that need "special teaching" are those which are subsets of mystery-cult guidelines, like those of Merinita or the Cult of Orpheus.
RoP:D, on p.21 states that Angels can be affected by Hermetic magic, including warding and "might draining" (all the way up to their destruction) even though it's not widely known. The only limitations are that they cannot be summoned by hermetic magic, and they can never be compelled to act contrary to their nature.
This statement is mostly true in the sense that it is vague enough that it hides where it isn't very accurate. What do you mean by "normal"? If you mean fully integrated into Hermetic theory, then no, the statement is not true. You can invent a new range/duration/target/guideline of some sort that wasn't in Hermetic magic via original research and fully integrate it into Hermetic theory. At that point anyone who has learned it can use it just like any other guideline, but those who have not specifically learned it cannot. Eventually, if it's not kept too secret, it will spread around the Order. If the guidelines are restricted to only certain groups, it could be this mechanic that is showing up.
First, the latter does not follow logically from the former. As I explained above, there are other ways this can come about within the rules. Also note that the other group that uses those guidelines is written up extensively and doesn't have a Mystery Cult Lore, which should make you wonder. Second, RoP:tI does not say the Venatores instruct the guidelines anyway. What it actually says is that a Vendatore teaches "what he knows about Demons and the Art of Vim." It also says they have their "secrets and techniques." They could teach Infernal Lore, Vim, and a bunch of specialized spells that have been developed over the years. Does that satisfy the statements in RoP:tI while still leaving the guidelines available to any Hermetic magus? Yes, it does. Third, since there is no statement implying membership in a Mystery Cult is needed to use the guidelines, I'll take the line editor's word on this one. He prohibited inclusion of guidelines that require Mysteries in the pdf, only allowing those available in general to Hermetic magi, yet these guideline were included without issue.
Technically you can't reproduce even a teachable breakthrough until you've "invented" an effect from an existing lab text utilizing that breakthrough. So the Ventatores could keep this secret without it being a Mystery. It wouldn't be easy, but these guys seem like people who would be really hard on anyone who stole their secret. The overall Order has kept Parma Magica exclusive for centuries after all.
I don't think that's what's intended in RoP:I but it could be a fun way to play it.
Exactly, though I'm pretty sure the rules don't require you to reinvent someone from a lab text specifically. We have a non-Mystery Cult way of keeping such things secret. This means maintaining and teaching such a secret does not imply a Mystery Cult.
Remember, RoP:tI doesn't say the guidelines have been kept secret, as I mentioned above. Also, as I mentioned above, HoH:S quite clearly shows the guidelines, if secret, are not secret to just the Venatores.