I updated the wiki with Roberto's spells. 
So, like, are Lucas and Roberto going to spend time teaching spells to each other? Or should we each write out a Lab Text Grimoire?
That was a question I had. They want to teach each other Spell Masteries. How does that work? Can they teach them in general? Do they have to teach them for an individual spell? How much time does it take? The rules don't really address that - at least not where I've looked.
If they were teaching actual spells, I can see the rules for that. If they were writing a tractatus on a spell mastery for a spell, I could see how to do that. But in this case, Lucas wants to teach Roberto how to use the Boosted Mastery (in general or for a given spell), and Roberto wants to do likewise for the Stalwart Mastery.
It does little good for Lucas to teach spells to Roberto, since the relevant spells he knows are "Boosted" spells, and only someone with Mutantum magic or Boosted Magic can learn them. They're not spells that Lucas has the spell mastery "Boosted" for. Lucas does it without need for the mastery. It's just that he can teach others how to master spells with the Boosted mastery. Besides, I think Roberto and Lucas know some or all of the spells in question. For example, Lucas wants to master Leap of Homecoming as Stalwart. But he already knows LoH and doesn't need to learn it again.
Do you know how we go about this?
:-/
What we may do is this:
- You practice your spell mastery a season, as usual, with the other mage giving you advice on how to do things. By the end of the season, you've got the spell mastery.
- If the other mage has spell mastery for that spell, he can teach it to you instead, which supposedly gives you more XP and is guaranteed to cost him a season.
Options:
- Learning the mastery
- The other mage can only tutor you in the spell mastery, gaining exposure XP. This means that both Roberto and Lucas will each need to spend a season.
- The other mage can practice along you.
Although the second option doesn't look unbalancing, I'd advise against it, as it greatly devalues being taught Spell Mastery by someone else: Roberto and Lucas would each gain 5xp in a season, then be free to do better things, whereas, if they could teach each other spell mastery, they would waste 2 seasons for 6xp for lucas (Roberto SQ 4 + exposure 2) and 11xp for Roberto (Lucas SQ 9 + Exposure 2).
Being taught a mastery would take more time for less XP, on average! This is not cool.
=> What I propose:
- You must practice Spell Mastery under the other magus tutelage, or being taught it by him. The other magus gains exposure XP. However, if both magi are willing to practice the same spell, they can synergize and do it in one season, gaining both Practice XP in Spell Mastery as well as sharing their masteries.
This means that, [strike]usually[/strike] hopefully
Practice different spells < Being taught Spell Mastery < Working together on the same spell. I like that.
14xp total (7 each) over 2 seasons < 17xp total (6 for lucas, 11 for roberto) over 2 seasons < 10xp total (5 each) over one season.
- Scope of the mastery.
- You can only apply it to a given spell, or similar versions.
- You can only apply it to a given TeFo
- You can apply it to any of your spells.
It's a stylistic choice, which will greatly impact availability on a given mastery in the saga, as well as how "precious" it is, and thus how much a maga can extract for her teaching. Both have advantages and disadvantages for PCs.
It can go all the range from "Lucas told me his secrets, I don't need him anymore" to "Lucas taught me how to Boost my Pilum of Fire. It is great, and I applied it to great effect to BoaF. But I'm at a loss on how to do it with Leap of Homecoming, I need to convince him to tutor me again".
What if you wanted to use story xp from a story you were both involved in?
Here are my thoughts. Getting a spell mastery is hard enough. Absent a tractatus, it takes two seasons to accumulate enough xp for a single mastery level in a single spell. To add another one or two seasons to learn a particular mastery for each individual spell would make it prohibitively ex[pensive and out of keeping with other costs. Limiting it to a TeFo sounds like a lot of bookkeeping, and isn't much better from a cost standpoint than the previous option, There are 50 combinations. Even if you choose a small subset of TeFo combinations, that's a lot of seasons to spend, especially in a PBP game.
Spending two seasons (teaching and learning) is a lot for an ability that will likely only get used a few times, even if it is learned across the board.
So I say, it should be once you learn it, you should be able to apply it to any of your spells.
That also makes it easier to spend story xp on Masteries, which seems a good source for mastery xp.
Oh, and don't forget the +6 to SQ for teaching a solo student. That makes things a little better.
I need to check the Mercere section of True Lineages, but I am pretty sure it is very much easier than that.
According to True Lineages, it is harder than I thought. Yet easier and harder than what Fixer proposes.
hurmmmmmm......
Practice XP is 5 for spell mastery. Practice one season, get Spell Mastery 1 
May I slap myself for forgetting that? I have absolutely no recollection of this 
You'd think this would come up often enough.
What does it say?
It says
[quote="True Lineages p. 99"]
Any time magi earn a level in spell mastey ability, they may choose from these special abilities in addition to those in ArM5, as long as some of the experience points were taught by someone with the Ability. Most magi in the true lineages prefer to share this specialized knowledge only with their apprentices, though their methods may be written down in books that anyone can read, and it is not impossible for a master to decide to teach a student with very similar goals and loyalties.[/quoute]
That is pretty restrictive.
Though that leads to some questions. Does this mean that Lucas has to know the spell that he's teaching the Mastery for? He can't teach Roberto to Boost a spell that he doesn't know? That's tough because Lucas know different versions of all the spells that are good for Boosting, Harnessing, and Tethering.
So how does someone learn a Mastery in general such that he can apply it to any spell?
Oh, right. For some reason I was thinking it was 4 xp/season.
Hmm, I would think that once you've learned that particular form of mastery for a spell, you could then add that mastery to any other spell. That would make sense how once an apprentice learns a particular form of mastery from their parens, they can then apply it to spells later in life.
To me, the more interesting aspect is the implied roleplaying piece. Specifically that most magi don't seem to want to share these masteries outside of their House. So for Lucas to do so, he would at a minimum be bucking tradition somewhat by doing so. I personally like this aspect, as it keeps them somewhat special.
Presumably such sharing would usually include a promise not to teach it to anyone else (sort of like Cow and Calf).