Technically there is one, in p. 174 (from which the problem stems):
It takes approximately one combat round to cast a spell, unless it is fast-cast. Thus, a
magus cannot cast more than one normal spell, or a fast-cast and a normal spell, in the same round. A very fast magus may be able to cast more than one fast-cast spell, but this is beyond most magi.
Of course, this only says that it's possible to fast cast, not that it's a given in any situation, since fast casting happens "as a response to an attack or other surprising event". I'd say the problem comes from the rules lacking a clear definition for reactive actions (different from a few other games where it's more strongly codified).
For me, "a surprising event" lacks a clear definition and is a weak anchor between rules and story. Why can't I fast cast when I suddenly, with very much surprise, decide that I want to? So I just ditch it. If fast cast is possible at all, then it should be possible to do it at will. Maybe the fix would then be in limiting what can be done with fast casting, or after fast casting. On that note:
I think I remember seeing a houserule once where once you fast cast you were essentially giving up your "normal" spell for that round... Which, I must confess, does agree with me.
Anyway, part of the reason I wanted to run a short, low-stakes combat was to test the waters with magical combat before we got to the part where we can easily blow up entire cities.
The biggest problem I see with this (other than the text contradiction) is that essentially fast-casting becomes a pyrrhic choice. You can spend every round fast-casting a defense, never able to go on the offensive, and be locked in a defensive position for the whole combat; or you can not defend yourself at all, and just rely on your natural hardiness or killing the opponent before they can hurt you.
If we need a counterexample, I'd point to Flambeau duels, which are literally just two magi firing off spells and fast-cast defenses every round, until one of them isn't quick enough with the defense and the spell gets through.
I'd say text clarification. It seems it was clarified by the line developers that the intent of p.174 was indeed that only one spell is cast every round (but I confess this is hearsay, I can't point you to the thread where this supposedly happened).
Still, there is an easy "fix": only cast one formulaic spell per round, either fast cast or standard. This still leaves the option of fastcasting a spont spell for defense, but sometimes if you have just the right spell for the situation it's better to go formulaic.
And fast casting a formulaic spell would still leave a flambeau with his sword and shield. Go Ramius on them!
Disclaimer: this is not a houserule proposal. It's more like an academic debate.
I'm talking more for general combat. Ramius isn't very Flambeau-like anyway.
The distinction would
allow for fast cast sponted defenses (against mundane or magical threats)
allow for the use of fast cast formulaic for the few cases where you need a specific and powerful spell (to strike first, to defend yourself, to escape, whatever your purpose)
remember that in this case the magus still has his action, which he can use for whatever is reasonable
limit the conjuration of more than one formulaic spell per round (they are reasonably stronger than anything that can be fast-cast sponted), which solves the problems mentioned above
we would also probably need to define that the activation of a magic item is generaly too complex or rigorous to be done in the same round you cast a formulaic (otherwise we have the same problems, but in another field)
keep most of the current rules regarding fast casting in use.
We could simply eliminate the formulaic fast-cast rules (which are the root of the problem here), but I find this to be an unnecessary and ungainly solution. We could also codify what is actually a valid trigger for a fast cast response and what is not, but I find that even more ungainly, by the virtue of being arbitrary and disconnected from the narrative.
I don't see any problem with what I'll refer to as the "normal" rules:
one normal spell, or a fast-cast and a normal spell, in the same round. A very fast magus may be able to cast more than one fast-cast spell, but this is beyond most magi
You framed it as a problem, and Arthur doesn't like it either, but it's been in every game I've played besides this one, and there was no problem and nothing wrong with it. I don't see any reason to change it.
Since it's such a small game, and it may not come up that often, I don't see what to say further; I'll just let it go with whatever you both are happy with, to keep the game alive.
I'm not proposing we adopt any houserules here (but if we do I'm not against it). Again, for me this is mostly an academic discussion. Something that I would like to see in a 6th edition, maybe? But if you want to end the discussion I will comply. ^^
I actually think the opposite. If it doesn't show that often, this is more of a reason to keep the rules as they are. If fast casting was a staple that happens at least once in every story, then that would be a strong argument to revisit the rules and ensure that they provide a satisfactory framework.
I think Telsberg Trouble will close soon. The main purpose was to present Otto's request and a few characters from the Telsberg family (I have a spreadsheet with a few more, but we will have time for that in the future. Haha).
Chronologically, Giant Problem happens about 4 months after that, and then, IIRC, the plan was for us to go talk to the magi at Rhine in preparation for the next Tribunal? My idea was to use Durenmar's library and look at the past Tribunal records for a season. For the rest of the year... Dunno.
However, I'd be happy to participate in whatever you have planned. The season of legal research may be delayed or deleted, depending on the whims of fate. =]
I have presented the "final results" to Giant Problem, but this is by no means to finish the thread. If we want to discuss the events of the season in character, or if Wolfgang want's to do something (e.g. talk to Orell, sell the skulls to him, etc), we can keep going for a bit more.
Not sure if you got to take a look at the other threads, @Arthur is our main storyguide, but the idea is that we all take turns and share the burden. It would be nice if you could indicate which kind of stories you'd be interested in running (or for which character you'd be interested in taking a more active approach). The Notes and Claims thread should have some info on who has commited to what (just so you have a notion, I think there is no problem with some overlap).