My new saga is set in the Greater Alps and the PCs are all apprentices. Two of them have Sabastien filius Luise, follower of Tytalus, as their master. He is briefly described in Sanctuary of Ice, p.70.
Sabastien specializes in breaking into the sanctums of other magi, usually on official business such as Quaesitor investigations, or on behalf of Covenants who have a member that has gone into Twilight and whose sanctum might be dangerous to explore. Timothy's writeup in SoI suggests Sabastien has various "tricks of the trade" which he uses to safely intrude on Sanctums and disarm whatever traps he finds there. Normally, I wouldn't bother to classify this more precisely, but since he is the master of two new apprentice PCs, it would be helpful to know his spells and other tools.
So I am asking for help from more experienced GMs. What spells or other tools might make up Sabastien's "tricks of the trade"? Please describe the effect as precisely as possible. Special points given to Rego and Vim effects, since his initial writeup says he specializes in those Arts.
I think "Image from the Wizard Torn" (ReIm) and perhaps an item "Opening the Intangible Tunnel" (ReVi) to the image does the job cleanly. You could cast "Opening the Intangible Tunnel", but considering how long it might take to search and understand a Wizard's Sanctum, I would hate to have to make all those Concentration checks.......
We have tended to use Sun duration Cr(In)An dogs, cats, salmons and crows to explore places. With an Intellego requisite to use their senses. The occasional maverick magus or familiar has also entered potentially dangerous places without previous warning (but on high guard). We do not go into magi santums so often, though.
As mentionned, InVi to detect any magical traps. You can expand Intellego spells to Te and He to cover many mundane traps as well.
Various Unravelling the Fabric of (Form) to easily nullify such magical traps. A strong Wind of Mundane Silence, mastered for fast-casting, would also make sense for general and emergency uses.
CrCo to create a corpse (perhaps even a copy of your own body), and ReCo to animate it so that you can walk it forward like a modern-day defusing robot. In combination with something similar to Image from the Wizard Torn (ReIm) or Summoning the Distant Image (InIm) so that you can see from its point of view.
ReCo to translocate directly inside of the lab, bypassing many of the defenses.
Good scores in Parma Magica, Concentration and Finesse are probably good guesses.
I want to thank everyone for their suggestions. I have added many of them, including a spell to create a human corpse and animate it, spells to summon and see through the eyes of a crow and salmon (I also added a Re requisite to control the animal), a fast-casted Perdo Vim spell, spells to both see through and transport through walls and doors, and some spells to see both magical and mundane traps.
Let me ask a silly question. Would a magical trap have Magic Resistance? Is there any way it could be given such Resistance? In other words, could Sabastien have a bag full of Wands of Unravelling, each keyed to a single Form and Penetration 0?
Pretty much, yeah.
Though ofcourse they're likely useless against things like a charged device designed to cast a D: Mom spell (ie. PoF or some form of PeCo) "at anyone but me passing through this doorway".
Coincidentially, that sort of trap is also fairly hard to detect, since it contains no Vis and has no active effects.
One thing he'll want is a spell to constantly renew the air in his lungs, another spell to fly, and a final spell to protect himself from the building collapsing on him. Its a pretty trivial spell to turn the air into acid, which while Parma would provide plenty of protection, it would also cut him off from the air entirely. (Or destroying the vitality/oxygen in the air would work too.) Similarly opening up a 20 pace shaft into the group would be rather lethal if he can't fly, as would dropping the building on him.
Off the top of my head, not generally, but it could get Magic resistance by being picked up by a creature with it, extending Parma Magic over it, or (for all intents and purposes) placing it in an Aegis of the Hearth. Now in theory an Aegis should run out after a year, but a truly obsessive magi might get around that too.
To add more explanation to Tellus' answer; one could have an intellego vim item with an effect like sight of the active magics (or perhaps invisible eye revealed) with a linked trigger to a perdo vim spell to dispel it.
The Hermanus chapter From Legends of Hermes has a slew of these sorts of set ups (intellego spells linked with other spells to go off when something is detected) in it. They're all non-lethal effects designed to slow up an intruder until the magi arrive, which I think is somewhat likely for a place where you'll occasionally have people that you don't want to kill by accident, but lethal effects aren't a particular stretch to design
This one seems to have gotten lost in the shuffle. It's a much more evil option but the use of ReMe to send somebody "expendable" in, possibly with an In requisite to see what they're seeing, could detect the otherwise hard-to-detect.
An animated corpse can do a lot but I think a mindless body might have the same problem I could see with using animals: bypassing triggers that function on InMe effects, designed to detect the mind of an intruder, possibly to detect if they are among the authorized person and not just shape-changed, or maybe if they know the password or some such. Neither a corpse nor a chicken would register as a human mental presence and, depending on the nature of the trigger, might just get ignored. Enter the overconfident magus, assured by his earlier explorations that all is safe, and BOOM!
If you want to send a walking corpse in to bring something back out, that seems a perfect idea, but it might not be so good if you really want to search the place thoroughly and/or disarm it permanently. A live person might be required for certain types of magical mine-sweeping.
I'm not familiar with Sabastien but, as a Tytalus, it seems likely he would be at least prepared for such an option.
A created body that is animated by a ghost would alleviate some of these issues (admittedly spells to target living and dead minds may be separate) with slightly less moral repugnance (and more work).
Getting applicable magic resistances of 100 for mind reading, mind control, memory destruction, and mental capacity destruction could be done with, for instance a parma score of 7 and a mentem score of 15 (or parma 8 and mentem 10) then mastering four spells for defense at a cost of 5 xp each. This seems to be a possible precaution for taking a trip into the lab after the corpse/ animal reconnaissance and intellego vim from outside of the lab has been done. This would protect you from most mentem triggers and most of the things that stuff which has been triggered in other ways can do to your mind (unless you don't house rule penetration on charged devices and effect expiry in which case all bets are off in regards to the sorts of penetrations one could reasonably generate). You'd hope that things that can trigger in other ways will have already been triggered and stuff that does things that targets things that aren't mentem has already been disabled. Getting this level of protection would take a great deal of work and might not be worth it. (Come to think of it I'd master a creo vim warping spell like "the enigma's gift" for defense as well.). An advantage here is that you can tell when your parma stops a spell and get more information.
Perhaps a rego vim spell container (like patient spell) of duration diameter or concentration could be used to simulate your "canary" (animated corpse/controlled animal/controlled peasant what have you) casting spells within the laboratory would be a good idea.
You'd also want to find a way to break circles within the laboratory once you know what spells the circles held (one could rig up a design to destroy the lab when a circle is broken so let's not be too hasty in their destruction). I think that your "canary" could typically do this.
Direct detections effect are usually made to target mundanes, otherwise it can be blocked by Magic Resistance. You can get around that by uilding in a lot of Penetration into the effect, but there are limits. I think most paranoid magi would rather assume that intruders would be protected by some form Magic Resistance (either Parma or Might), so would link any trap on some indirect phenomenom such as the opening of a door, weight placed on a carpet, or something similar.
Sabastien is described as very secretive, but nothing in his description suggests he is evil or the sort of man to mind control a peasant and send them in to a sanctum. There's more than one way to skin a cat, and there are plenty of great suggestions in the thread, but that one would not suit him.
I wonder if a minor magical focus in traps might be possible? And the Rego Vim effect to suppress a spell cast by another (device). Chances are the focus may not apply to inventing the spell in the first place, but during casting it would apply during certain situations.