My dislike of Mythic Blood is that the fluff and the crunch are pulling in opposite directions. The ability to pull off level 30 effects without fatigue is only really useful in very short campaigns (which very few people plan on being in, regardless of the reality of how often campaigns falter) or if the effect is outside the player's plan for the character.
Which means the fluff is saying "You are the descendant of a mighty being whose feats of strength in the field of illusion are sung until this day". but the crunch is saying "You only really want at will invisibility, you can now safely ignore getting Imaginem above 5, negelect it and concentrate your study on what you really want".
I'm not sure I have anything constructive to add here, merely setting out why the Virtue never appealed to me.
I do not think it is underpowered, and clearly not clearly so. However, as the clearly underpowered virtues (secondary insight and elemental magic) get revamped, one does start to wonder. You have started a chain reaction of errata (for better or for worse).
However, as @callen and others mention, the minor magical focus, barring any other focus, is unfortunate. For me that is not a power cost, but a loss of freedom. Why can't I make a Tremere with Mythic Blood? Why can't I make a Mythic Blood with a Major Focus (even well aligned with the blood line)? If anything, this is where I would suggest a change.
This depends on how you play reactions to the Gift in your troupe. If we just assume that the major Hermetic virtues are equal value, we just have to play harsh reactions to the normal Gift. Say, have the magi accused of every little crime in the area when they pass through. If a magus makes the mistake to address the mundane people, they are scared, and will no longer talk to their grogs either. Yes, this is an RP challenge, and it may be difficult to afford in a fast paced saga, but the genre of saga where Gentle Gift is more powerful than flawless magic does exist.
Yes, this is a problem with the virtue. To get maximum effect from the power, it should be something that you can't easily do otherwise. I.e. it should be something where your Arts are weak.
But from a thematic point of view the free power should probably be in some area where it overlaps with your magical focus and where your arts are strong - in which case that free power becomes close to worthless since you can easily duplicate it with a spell.
Since a lot of Mythic Blood is open-ended (choice of power, choice of focus, choice of personality flaw), it can be underpowered or a fairly strong virtue, depending on the choices made - and also depending on how often the fatigue-saving component comes into play which can vary a lot between characters and sagas.
Not only Tremere, but any of the other lineages that have a mandatory focus (Leper magi, Titanoi, Pharmacoepians, Pralicians, Hermetic Sahirs, etc.)
I don't think this is something that can easily be fixed with errata, but is rather best solved on a case-by-case basis by dialogue between player and SG, to change one of the conflicting foci to something else - Potent Magic being an obvious option, but not the only one.
One point that wasn't mentioned is that the power is a bit more powerful than a regular lvl 30 spell.
you can invoke at will and cancel at will
takes as long as fast-casting a mastered formulaic spell (I read from this that it can be fast-cast, but without the -10 penalty since it isn't a hermetic spell)
since there isn't a casting total, there is no penalty from foreign auras
So it is stronger a regular lvl 30 spell, but by how much is something that depends on a lot of things.
I agree that fluff and crunch are pulling in opposite directions. To me what should make this virtue shine is the power, and in my opinion it is pretty hard for a power to do that (well, I might not have tried hard enough).
The first time I thought "oh, this is really nice" was when I saw Hugh of Flambeau's power to create armor (and still, with his mMF it should be easy for him to CrTe one with a hermetic spell).
I'd mentioned the fast-casting above, comparing it to the level-30 spell with 5 experience in spell mastery.
Also, not rolling doesn't mean no bonus nor penalty from friendly or foreign auras. That just goes to penetration. This could be a plus or a minus.
I'll do some other bullet points:
Since you're not rolling and it's not a spell, you can't get big penetration (flip side to a bullet point above), especially as your Arts improve. The meager penetration you can get reduces your levels available.
You cannot improve on it with Spell Mastery like you can a spell. For instance, you could get Quiet Casting or Still Casting with a level-30 spell, but that would have to come out of your levels available.
Yup. That's the typical issue. Many of the canonical examples have an effect that isn't so far from the mMF, so the character is likely to have decent or good Arts surrounding this power.
I think the fluff and crunch are only pulling in opposite directions if you assume that mythic blood suggests a particular future, destiny, or strength in hermetic development. If my ancestor was a master of ilusion and dealt with the fae regularly and managed to contrive that his descendants would all be able to turn inisible at will that does not mean that I am slated to become great at imagonem, and further more would see les use for it than most since I can already turn invisible. If My great grandfather was a dragon and so I can belch fire that does not imply a mastery of ignem. If my ancestry suggests I will be a master of an art in the future then I should take affinity instead of mythic blood and just pencil in an appropriate heritage as the fluff for that virtue.
There is an issue here where to get the most out of the spell-like effect it needs to be clearly distinct from the arts you'd typically use with the minor focus (because otherwise you'd be better off learning it as a spell). I'd prefer this to be a minor virtue that only grants the fatigue effect but which is typically paired with the other virtues and flaws suggested in this thread / in the current description.
I must say that I agree with just about every post by Callen on this matter.
I love the fluff of Mythic Blood.
I don't like the crunch at all.
When I want the feeling of Mythic Blood ("you have a special ancestor"), I just take Magic Blood (which may include a free power), which feels a lot more coherent, and, if I want, assorted virtues.
To elaborate:
The focus is fine, save that there are issues, as mentioned above.
The power is mostly a small added bonus, save if you take it in an area in which you plan a deficiency, which, IMO, runs counter to the spirit of the virtue (Due to your ancestry, you should be good at x and y).
The fatigue... Well, IMO, there are, roughly, 3 kind of spells:
a) Those you want to be able to cast reliably, because they'll need to work now. So you ensure that you have the casting total for it
b) Those where you may afford to spend a little fatigue and rest.
Mythic focus doesn't help with the first type of spells, and is a minor boost on the second. Most notably, it is useless with spontaneous magic, which is the area in which you may have to cast a spell now and expand fatigue.
I've considered replacing that part with extra fatigue levels that you can only spend on spellcasting (which would be useful with all kind of magics), but could never test it.
Now that I think about it, focusing the virtue around the idea that "you have a wellspring of power inside", I'd probably go this way: give extrafatigue for spellcasting, and the ability to spend these as vis.
tl;dr: Underpowered virtue with great fluff that is better represented by a combination or other virtues.
Looking back over this, all the comments disagreeing with me on the point evaluation are roughly pointing to "no, this isn't worth a little under 2 points of the 3 invested, it's worth a full 2 points of the 3 invested."
Let's make the evaluation a little simpler. We know the Focus and the Flaw are worth 1 and -1. So let's only look at the rest. Are (no Fatigue on Formulaic spells that succeed) + (the 30-point power) + (the later added access to Heroic stuff) together worth 3 points?
Not sure about the extra, use-restricted fatigue and how to make that work well but replacing the fatigue bonus with something like Imbued with Spirit of [Form] (but without the onerous negative of pissing off creatures of your likely strongest Form because you didn’t consume a spirit, you were born that way) is one method that could give the sense of a wellspring of power. I’m sure there are other ways too, I really like the “wellspring of power” phrasing for what do we want the virtue to do. Like those with Mythic Blood should be the “natural born magicians.”
Unlike Mercurian Magic, an included personality flaw doesn't bother me too much, because those tend to be mostly fun rather than an actual flaw. I think the ability to save on fatigue to be the great benefit of the virtue, although I haven't used it very much in play, there is benefit in my view to be able to focus on learning high level spells not requiring penetration and to know you can keep on going and casting without worrying about having to stop due to fatigue after a few spells. There are tons of effect where that is useful since you rarely build a magi with 15-20 in every arts. My main gripe with the virtue is the Innate Power which I struggle to find a use for whenever I consider the virtue. Still, there are some counterintuitive elements, for example, the fact the innate power doesn't draw on your spellcasting capacity, when the virtue requires you to be a hermetic magi in the first place. I would have prefered if it was a spell that used your actual spellcasting capacity and virtues, rather than an inborn, unevolving power.
Something like this: You gain an additional 30 spell levels during apprenticeship. Additionally, one of the formulaic spells you learn during apprenticeship may exceed the level limitations allowed by your starting arts and comes with 50 xp towards its spell mastery score. You may also dismiss this spell at will.
This lets you play on your strengths coming from the virtue - such as the magical focus and the ability to ignore fatigue levels from formulaic spell, and it keeps its value throughout the game as you develop your arts further. If you have virtues like Subtle and Quiet Magic, they factor in the power level, if you don't, you can buy those as spell mastery options if you want.
There's much less consensus here on whether, and how, this Virtue is underpowered than there was for the ones I have changed. More importantly, there is no easy, errata-level fix.
I don't think I'm going to do anything with this one. Thank you for all the input.
Yup. Withstand Casting is better. Lesser/Personal Power are slightly weaker in some ways (fast casting, 5 levels, Fatigue) while being slightly better in other ways (non-Hermetic allowed); overall slightly weaker. A noticeable gain in one v. a noticeable loss in the other. Saving your Major Hermetic Virtue about balances losing the Heroic opening, and you can adjust this for a Tremere or ex-Misc tradition. But now you actually get the value for taking your Minor Personality Flaw. Or you include that Flaw and bump up Personal/Lesser Power, making them better than this Virtue's power. I just find it sad that the advice for a nearly perfect fix is to probably never take this Virtue.
Of the three minor virtues you bring up, withstand casting seems to be the one which is most intrinsically tied to the bloodline. Thus Mythic Blood should probably be a minor virtue, equivalent (or similar) to Withstand Casting with added fluff.
The other to may be suggested or recommended to go with it, but at the end of it, each player may design their own blood line with a lot more flexibility.
(Or we could call it a fluff-only free virtue with no mechanical benefit whatsoever.)
I didn't think of withstand casting. Yeah, it does look like the main benefit of Mythic Blood has been diluted by further publications so that the virtue is no longer a virtue investment that makes sense.
The Withstand Casting virtue is nowhere near as good as what you get from Mythic Blood.
Withstand Casting reduces your fatigue loss by one level, but if you were going to lose fatigue you always lose at least one fatigue level anyway.
Mythic Blood on the other hand means that you will not lose any fatigue at all when you succesfully cast a Formulaic or Ritual spell. And it will reduce fatigue from failed rituals more than Withstand casting would.