Players can discuss the development of their characters here.
Trendaline of Bonisagus is someone of your creation, probably a trianoma filling the Tabula Geographica Magica. Is that a NPC we can use as Mater ?
I happen work on a background where a Trianoma finds me by monitoring local village folk witches Does it bother or on the opposite is of some interest to you if she's my mater ?
Tandaline is one of the maga of Durenmar, described in GotF. She is indeed a Trianoma, specialized in Auram magic. Up to you to determine if she is a suitable mater for your magus.
Are you set yet on the year of the beginning of the saga ?
I have 1197 popping up in my mind, but am open to suggestions.
I've been skimming through spells and guidelines with PeVi on the top of my mind. To me, Perdo is mostly good in combination with three Forms: Ignem, Mentem, Vim. Meanwhile, CrVi isn't so special, and I'm not going to focus in MuVi. So it looks like my Arts will be:
Primary: Perdo, Vim
Secondary: Intellego, Rego, Ignem, Mentem
I've thought up what I think will be an interesting Boni-snatched background. Quick summary: beginning apprenticeship as a Flambeau in the school of Apromor for four years, taken by Caecilius as part of investigating the parens who was then marched, then trained as a Bonisagus for eleven years, now trying to get out from the prior parens stigma by doing great deeds.
I don't know about that. PeTe can produce some spectacular destructive spells. PeAq effects can be quite deadly to all living things.
IMHO, PeVi tend to be a specialty niche that is good only against supernatural powers (creatures and practitioners). But to each his own! 
I'm looking at concepts, and it seems no-one else wanted to do Creo.
I'm thinking of:
A weather mage who is interested in developing a breakthrough around lightning (effectively giving scaleable guidelines for CrAu damaging lightning effects), but maybe this force involves interactions between substances he isn't aware of, and attempting to fit lightning/electricity into the Hermetic paradigm will require collaboration with his colleagues;
or a Terram specialist who wants to explore caves, is convinced the Merinita disappeared into an underground realm, and wants to devise a method of making a vehicle that will allow him to explore underground to discover if the reduction in vis occurs deep beneath the earth or not.
Well PeVi is probably the best combination of perdo by far and the 3 combinations you select benefit the most from high score indeed but PeCo and PeTe are not bad either.
There are a few other good application outside of perdo (PeIm for invisibility; PeAq(Co) Curse of the desert ignores armor for damage) but not worth specialising imho.
Sure, but that's why I said "to me." PeAq can only be so deadly when it's done with casting requisites, for instance. But PeIg can be nearly as deadly without any such requisites.
Yup. And I'm considering that we don't want to waste vis, so I don't want to do non-Infernal versions of DEO. Better to slay magical beasts in other ways.
They certainly have their uses. PeCo seems relatively inflexible, though. Knock of human Fatigue? PeIg, and it works for animal Fatigue. Damage a human? PeIg, and it works on many more things. Meanwhile, PeIg also manages darkness effects, which can be handy in whole other ways.
Yes, invisibility is great. But a moderate Perdo score provides for everything you need without any score in Imaginem.
It's also : concentration check, blindness, mute, deafness,crippling, disease, pain without damage (aka torture), aging and more importantly the last guideline"destroy one property of a person such as solidity" is basically immunity against all physical damage depending on SG's interpretation. That's not bad ^^.
Yes, destroying solidity is pretty cool. I'll probably go for that one eventually. I still won't need penetration for it unless I'm invading a foreign Aegis, though. As for the rest, I've never felt the need to do any of those. Why cripple/disease/blind/etc. someone when you can knock them out or kill them? Meanwhile, you can effectively blind someone or similar with PeMe, too. Any why use torture when you can PeMe their inhibitions to answer you? It's not that PeCo doesn't do anything, it's that once I've got PeIg and PeMe going, I don't see that I'm getting a much more out of PeCo.
Anyway there's so much to do with the arts combination you selected I doubt you'll miss an additional form before long.
Both concepts are viable, If you do the second he has to be a dwarf tough 
CrAu is fun. There is a lot of versatility within that one TeFo combo: attacks, defense, stealth, mobility, farming, and more. I'm a huge fan of Auram in general. And good Creo opens up healing a Vis extraction.
I see what Bitter means about dwarf blood. Sound like D&D gnome inspiration.
In looking at the Elementalist breakthroughs, I am wondering if I would need to do one of the minor virtues like Elementalist Water and then do Refining. Reading the part on integration (pg32 HM) it seems to get Refining it needs to be combined with the minor virtues. Am I interpreting this correctly?
Or does having Hermetic Elemental Magic cover all 4 of the minor virtues in Hedge?
Reading the section carefully, it seems that each Elementalist Art need to be the subject of a seperate Major Breakthrough. And you need 2 such breakthroughs before you can get any use out of it.
Hedge Magic p.33:
...This means that by adapting Summoning and Elementalist Air...
Some work may already have been done on that, so perhaps your character won't have to start from nothing. It all depends on what your avenue of research is...
Does change in duration from maintaining the demanding spell (diam-->sun) makes it a custom spell for the purpose of character creation ?
Also I'm considering Alyssa from through the aegis p 52 as my mater, but I would transpose her in the Rhine tribunal is that ok ? I guess you don't plan to use her as she's from the Provencal tribunal.
Actually, it was inspired by the sidebar in Against the Dark about Tremere having vehicles built by Verditius, and possibly getting player magi to investigate if one goes missing. The fact that the Rhine Tribunal has stories of Nibelungen and koboldi makes for interesting Terram-related stories, as opposed to the versions filtered by D&D copying fantasy novels that copy Tolkien's version of Nibelungen. Also, the possibilities thrown up by Art & Academe (is Hell literally below us, not metaphorically? Is Pliny correct in saying gems breed deep below the earths surface) add something.
Having tried to design an underearth vehicle, I think I'll try the Auram mage - it's more straightforward as less likely to need big negotiations as to whether it's workable or not.