Arrgggh! I just realized I brought a lot of Rego and Muto vis, but only a little Corpus! Doh!
I'm going to attempt to shift the battleground.
Let's follow the Ig = light, Im = paint metaphor a bit further.
So, under this assumption, we're talking about the flash-bang effect because it seemed like an obvious illusion to attempt, but the core desire here isn't to create the flash, it's to temporarily incapacitate the target's vision.
So, instead of a flash-bang, how about filling the target area with visual noise? What about a spell that flings an illusionary starfish onto his face? What about a spell that encapsulates his head in a helmet with no eyeholes? Cause the room to appear to be filled with jagged spikes? Fills the space with fog, or swirling psychadelic colors?
The problem that I have is that the published Imaginem spells haven't been creative enough. Check the Net Grimoire for some slightly better examples:
Conjuration of the Insubstantial Blindfold
CrIm 10, R: Voice, D: Sun, T: Individual
The image of a blindfold is created around the head of a creature. this image will move with the creature's head but it can not be grasped or physically interacted with as it has no substance.
(base 1, +2 range, +2 sun, +1 moving image)
Contributer: Tyrrell
Notes: From the message board level10-15 spells project.
For me, if I'm going to get good and flexible with Imaginem spells, I need to start by picking a general theme for your Imaginem habits. Sea themes? Forest themes? Faerie theme? It's the key that leads you deeper into the potential of illusions. For example:
"I want a squid to wrap itself around his head."
"A swirl of leaves lands in his face and cannot be removed."
"A horde of buzzing pixies dance in circle before his eyes."
They're all the same spell, but from each one I can reach towards other spells which I might want to try later. They inspire future spell creation while providing character color.
(tangent: short magi could create a spell which fills an entire room, at human head height, with visual noise. That'd be quite an advantage.)
I love it but I would not do it mainly because Jacques has an Imaginem score of 0. I'm trying to be creative on a budget 
It's an interesting spell, but I don't think it can work as intended, to move about the creature's head for the period of time indicated. I think it makes an assumption on the CrIm guidelines that isn't correct.
Reading the guidelines for CrIm it says, increasing the complexity such as "making a moving visual image" adds an additional level of magnitude, and then in the next sentence, "[m]aking an image move or make noise at your direction as you concentrate adds two levels of magnitude." If one could create such a spell, with only a +1 magnitude, why is there even the description of what the +2 magnitude can do. Further, I believe that CrIm creates an Illusion at a specific physical spot, not a spot that is immediately in front of a specific target's eyes. To be able to constantly move in front of the eyes of the target would suggest some sort of Intellego effect, and if that guideline is higher level, which I think it might be, then I'd be inclined to go in that direction.
I think +1 movement allows you to "program" a preset routine into the illusion, but it isn't capable of dynamic interaction as described.
Mercurian Magic is the suckiest of all major virtues. I hate being crippled when it comes to spont magic.
Well, originally all this would've played out much differently, but I always figured you'd end up here, and the same scenario would've been going on...
I'm aware of your limitations, someone will be dealing with the fires, but in a situation of mass choas, it takes time to get things going and communicate effectively, even for Redcaps. So, Korvin does have a way to be helpful; that explosion has an effect.
Alternatively, we can discuss some better spell selction, and/or possibly a different virtue. Mercurian is nice, but it requires a vast amount of planning to have a broad repitoire of spells. In hindsight, that's really difficult to do when you spend XP to acquire initial spells.
And by this, the events related to Apollodorus identity becoming more common knowledge.
Is Xenophon someone in the books, or entirely your creation? I don't recall anything about these Duresca Scrolls.
Xenophon/Apollodorus is my creation.
The Duresca scrolls were a collection of documents that were letters between Guernicus and his filii describing a secret agenda of the House to take over the Order, and then eventually the world. They were discovered at thecovenant of Duresca in Iberia. They were presented at the very next Tribunal, but declared fraudulent and destroyed. Soon afteward the purging of House Tytalus became necessary, and distracted from the controversy. And then there was the Schism war that happened, soon after that.
I decided to blow the lid off this a bit sooner than I had initially planned. It also works well that Apollodorus' plans fall entirely apart because of an inadvertant comment from a lowly Tremere soldier who's just read a bit too much for his own good.
I want to make sure you know that I am more than willing to revisit this. If the Mercurian is too difficult to play we can come up with something else. AFAIK, the only places this played out was 1) The Dimicatio 2) the spell to move Mufarjj and 2) The spell to heal Mufarjj. So the impact of a change, IMO is relatively minor, we can account for the vis, and the other two items can be handwaved away...
That is mostly because I have tried to avoid times when I have to spont cast a spell. I was waiting for another mage to show up during the 45 minutes it took me to cast the spell to move Mufarjj to just cast dangling puppet and move him rather than wait. It will be useful when he has to cast healing rituals but not casting AoH.
It is more of a complaint about it being a major virtue. I took it because it fit the house and story but it is very limited gain for major drawback. ArM system rewards creativity for thinking of spells or how to do things with magic. Most of that tends to be the spontaneous magic system. While Korvin can do spontaneous magic it takes so long that in a situation where I do not have 15 minutes to an hour to cast a spell it really sucks.
Now if we were a vis poor campaign it might be different but using 1/2 vis on rituals and a spell that only works if others take it for hurting spont spells is just not worth the 3 points. Comparing it to any other Major Hermatic Virtue leaves it wanting in a big way.
I'm done ranting
I will say, again, it could be changed. Mercurial works, but I think Mercurians need to have a vast repitoire of spells. You could rework your grimoire to some extent.
Oh and this story is mainly about the aftermath, so your Arts will come into play.
Not that it makes a particular difference in the battle, but I cannot believe that I totally forgot that Fiona had some armour commissioned over a year ago. I'll just assume that, since she's not used to wearing armour, that she forgot to go put it on when the alarm sounded. And I'll need to write it up. Ideally, since the covenant is Wealthy, we can afford to make her oversized Chain Mail (presumably using the normal Protection and Load values). If not, then Metal or Leather Scale (preferably the former, since it has more protection).
And in a related vein, I also realized that I never bothered to actually write up the armour part of The Armour That Fits that Fiona brought with her. It's MuAn(Te), with the requisite for the iron fittings on the armour. Unfortunately, Leather Armour sucks. Would it be feasible for it to be Leather Scale or Metal Reinforced Leather with that item description, or is Ivor just going to have to suck it up? (I glanced at the MuTe guidelines, and reversing the Animal and Terram is going to mess up the calculations).
I was just mad because I was thinking of ways of putting out the fires which would be interesting since Korvin can't do Perdo well at all. I had some good ideas then realized I could do none of it. Just pisses me off that Mercurian is so poor of a major virtue.
Once again, I heartily offer Theraphosa's skills in OoHLore5, and other such mundane knowledges.
Hmmm...does learning from a familiar count as the "one season a year"? That would be an interesting precedent...I think in most cases, you are legally your as far as responsibility and tort goes. If your familiar steals a shiny pawn of Vis, it's just like you did yourself. But there's still room for doubt.
I wonder if Apprentices will address this when it comes out?
Although, whether he winds up Triamoran Bonisagus or Guernicus, he's going to need OoH lore, I think. So let's pencil him in for whenever Theraphosa wants, pending legal counsel against it.
Would have to be Winter. Possibly, she can ask about the legality of it in her Correspondences on CoH ~snicker~
Hrm. I see that according to the rules, Thera can teach 1 student, even with Teach 0, but only gains Exposure XP in Teaching. I'd like to argue that it would count as Practice XP (5), since she'd be "forced to practice [it] in an environment with immediate feedback as to how well you are doing."
Let's see, Com 3 + Teach 0 + 3 + Single Student 6 = 12.
If we can get her up to Teach 1, then she could take on Abagael filia Korvin as well. ~cackles at the visual~
Shall I adjust my Seasonal Activities?
Or we could ask our local Guernicus maga, if she's still around.
Sure. That's when I had Ulrich penciled in for being taught anyway, so it works for him.
Again: Light is NOT species.
The fact that this spell requires an ignem requisite to create light at all clearly show that:
Imaginem = species and not light
Ignem = light and not species
There's not a talk of affecting lungs.
If you go saying that Im can create light, and light bright enough to hurt, why not say that imaginem can create foul smells like wreath of foul smoke?
Note that I can take your argument in reverse, in that, even if accepting the notion that Imaginem can create light (which, by the raw, it can't), "your senses might tell you it is blinding but it does not blind".
Well, thanks. I'm relieved. It was a concern to me, and I was bothered by this.
This is interesting. You might want to ask this to... Timothy Ferguson, I believe? Or at least someone more versed in this by me.
I fear this may be something akin to Pink Dot, a discrepancy in the rules.
Yes, this is how I understand it:
If creating an illusion that also emit light, you must use Imaginem (for the illusion) and Ignem (for the light).
Whether it's CrIm(Ig) or CrIg(Im) depends on the highest base.
Oh. I just realise I missed a lot of discussion here, as I'm 2 pages late 
Serf's parma, this would work.
See miniatures, in the Jerbiton section of HoH: S, this (IIRC) covers exactly this kind of thing (aiming an illusion at someone's face). Johnatan has quite a good point about magnitudes, though, and I don't know if this adresses it.
Yup.
For rituals, you need to think BIG.
It also helps if the GM ensures that some spells are rituals due to their potency, meaning they become your specialty.
One (IMO) excellent HR that I found in the army killer spells was that any spell with something like Group + 3 magnitudes for size (I believe it was 3, but am unsure) was a ritual. This insured that almost all the spells of mass destruction/manipulation/whatever were rituals, and thus the domain of excellence of mercurians.
Let the smaller magics to other magi! And boost these Artes Liberales and Philosophiae! A non-negligible part of sponts in done ceremoniously, anyway.
So have Isen, fiona, alexei and the rest clean up the carpet... Add a magnitude, and clean the carpets!
So try to learn or develop useful rituals. These may be because of level, size, duration, or just raw power. Boost AL and philosophiae. You could be our magical artillery/mass builder/whatever! Send letters to other mercurians, asking for rituals they may send you... Even if it takes 2 years to get them, once you have enough, you can learn them.
hope this helps at least a little
Exposure, not practice. Practice involves deliberately trying to find out more about a subject, in this case, Theraposa would be trying to figure out more about teaching. However, since her primary activity is imparting her knowledge to another, she can't practice teaching to the exclusion of everything else, and it must therefore be exposure. She picks up some useful tips as she gets feedback about how Ulrich is absorbing material.