I've been reading about Wizard's Communion & Mercurian Magic.
This quote from ArM5, pg 46 in the Mercurian Magic description has gotten me wondering about further things.
When casting a spell using Wizard’s Communion, you may add your Mastery score (page 86) in the spell being cast and your Mastery score in Wizard’s Communion to the effective level of the Wizard’s Communion.
To me this begs the question of what benefits other than this that someone should/would get out of investing in a strong Spell Mastery of Wizard's Communion? Is there a point to doing this?
Strong, maybe not, but at least some, yes. Imperturbable Casting is good, as well as the general reduction in botch dice (to potentially 0) you get from Mastery. Look what happens when you fail your Concentration check. There are a bunch of ways to fail with Wizard's Communion. A single point of Mastery to pick up Imperturbable Casting helps significantly toward both. At that point, I'd probably pick up Adaptive Casting rather than repeatedly Master different levels. So it seems like Mastery 2 should be a big target.
And then do the same with Wizard's Vigil / Day of Communion.
If you can get the specialized tutoring to learn some of the less available Mastery abilities, maybe a combo of Adaptive Casting, Multi-casting, Tethered Casting (and maybe Fast Casting if you want to try battle communion?)?
I had considered that. The problem I see is three-fold.
The first is just a difficulty thing. Consider the Concentration needed for MuVi. Now you're doing it with a pile of things at the same time. That will blow up quickly.
The second and more important thing is that Wizard's Communion is written in terms of the number of magi manipulating the spell via MuVi, not the number of MuVi spells.
The third thing is just a question of value. Do you want all magi to be Multiple Casting Wizard's Communion for their own spells any time they want lots of penetration? Basically, take two round and you get immense penetration with even high-level spells?
I'm not sure how you could get this to work. The "appropriate target" is the soon-to-exist spell, but you have to cast this spell before that spell gets cast.
To what end? Is there a reason to expect to lose more than a single Fatigue level when casting Wizard's Communion? I could see it with Life Boost, but then you don't get the benefit of Life Boost, so that circumstance of losing more than a single Fatigue level doesn't qualify.
Also, isn't Withstand Casting a Virtue rather than a Spell Mastery option?
Sorry, I confused the virtue with the spell mastery - "Stalwart casting" from True Lineages is the spell mastery option to reduce fatigue loss.
Now here's an idea: Does the Rebuttal mastery (which affects Muto or Rego Vim spells designed to affect someone else's spells or powers) count for using Wizard's Communion (A MuVi affect) on someone else's spell?
Yes, that's not a bad option since you probably need to use this for combat purposes or in other difficult circumstances. I say that because if it's a Ritual, then Wizard's Communion doesn't work, and since the level is 50- a magus who knows the spell can probably manage it unless penetration is an issue or you're in a bad aura. Penetration is most likely to matter in bad circumstances, and bad auras would be bad circumstances, both places you might want to hang onto those Fatigue levels.
It does not work. However, I don't see why you could not invent a version of Wizard's Communion that does not work on your own spells, and then you could apply Rebuttal.