Of Taint and Tome

[Xuldarinar]

What sort of interactions should exist between the magics of the tome of magic, and taint? For instance, if a taint system is in play, should binding certain/some/all vestiges put the binder at risk of accumulating taint? What about mysteries? What about saying certain words with truenaming?

How would one go about making/adapting Tainted PrCs for these magic types? I know a version for Shadowcasters wouldn't be necessary because they qualify as is for the Tainted Sorcerer, though most of it's class features will have no effect.

[Psyren]

An easy one for Truenamers would be letting them incorporate Dark Speech into their Utterances, gaining benefits like an untyped bonus to Truespeak checks = their Taint score as a result.

Taint is similarly easy for Shadowcasters - simply do what PF did and tie the Plane of Shadow to the Negative Energy Plane, or do what FR did and tie it to an evil-aligned Shadow Weave. This can become a spiral - use of Mysteries grants Taint, but more Taint grants bonus Mysteries, which the class sorely needs.

I don't really like the idea of tying taint to vestiges, because they're supposed to be amoral rather than immoral. But there are other mechanics from HoH that can interact with binding; Phobias and Obsession fit vestiges quite well, particularly to Binders that fail their binding checks and fall under the vestige's unnatural influence - gaining an aversion or perversion towards the things the vestige itself desires or fears. What's more, you can have certain areas of the world be so alien and paranormal that they empower the vestige, causing the Binder to be treated as though he made a poor pact while he is inside even if he had previously succeeded, and placing him under the influence of one or all of his vestiges until he can successfully escape that region. You can say that in areas like that, "the veil is thin" or similar. And finally, you can say that a Binder's practice of opening up their soul to vestiges makes them easier for other kinds of beings to possess, especially in the small hours before they successfully form a pact. (While they are pacted though, they should have extra protection.

[Xuldarinar]

Those are some great ideas. Would it be unfair to say that taint would then fix one of the biggest problems with the truenamer?

I agree that it is something the shadowcaster sorely needs, which the fix by one of the authors of the ToM includes, bonus mysteries based on charisma. Though I'm never certain if the RaI is that these bonus mysteries are for each mystery individually, or are free floating uses.

I understand not wanting to mix taint and vestiges, for that very reason. The only ones i'd think it would potentially make sense for inherently are for vestiges that were previously demons, devils, and the like.