Learning Supernatural Abilities in play

[Einauge]

@Erik_Dahl

“Characters with favored Abilities must subtract the total of all their Supernatural Abilities, including favored Abilities, from the source quality when learning Supernatural Abilities that are not favored” is clear, but similarly wrong, I think.

It’s not wrong, it’s a direct quote from Rival Magic p. 9. RoP:I is the only book to say that you “do not need to subtract their scores in these [Favored] Abilities when learning other Infernal Supernatural Abilities.”, and restricts it to other Infernal Abilities. Other books are silent on the issue or say the opposite, such as RoP:F p. 118

The scores in non-Favored Supernatural Abilities still penalize the Source Quality when learning Favored Abilities, and vice versa.

This matter was already discussed in another thread:

RoP: Divine Questions

As far as I know, the intention is was for Favoured Abilities/Arts to work the same everywhere. If the rules are apparently different in different places it is (I think) merely a mistake and comes down to different authors writing different things and mis-understanding the others. The version that I prefer is that in Hedge Magic. There the rule is that: When you learn a Favoured Supernatural Ability/Art for the first time you suffer no penalty to your Study Total (due to existing Supernatural…

Your co-author Richard Love argued for the other position:

@Richard_Love

The version that I prefer is that in Hedge Magic. There the rule is that:
When you learn a Favoured Supernatural Ability/Art for the first time you suffer no penalty to your Study Total (due to existing Supernatural Abilities and Art Scores.
When you learn a non-Favoured Supernatural Ability/Art for the first time, you suffer a penalty to your Study Total (based on all of your existing Supernatural Abilities and Art Scores; including favoured ones).

Just from reading the books, it seems that how favored abilities work in RoP:I seems to be an exception.