I'm currently introducing friends to Ars Magica, and after a first adventure run which introduced them to Mythic Europe (without any magi at all, to reduce complexity), I'm preparing the free Nigrasaxa adventure. I was expecting that someone had already converted it to fifth edition, but could not find anything on the net, so I'll share my first steps.
Converting the PC's was mostly unproblematic - I gave Ariel an MMF to bring him to 3 virtues/flaws and eliminated Weak Writer from Herrit. For Morlen, I replaced Obligation with Faerie Friend and eliminated Poor Reader. Siffed got Warped Magic and Weird Magic to bring the number of flaws up to five. For Thamik, I replaced "Follower of Verditius" with "Difficult Spontaneous Magic" and decided to keep "Deep Sleeper", even though it is not a Flaw under ArM5e rules. Adapting the known spells required some intuition
Converting the library of Nigrasaxa was more challenging. I converted all the libri quaestionum into tractatus, simply because a liber quaestionum may only be used once. Since book quality works differently in ArM4e, I decided not to try to calculate equivalent values but just went with values that seemed right. Quality should be higher than in ArM4, because quality is directly the number of xp you get (barring virtues), and Tractatus by the same author should have the same quality. The quality of tractatus by Maximianus of Bonisagus is unformly 8 (I just assumed Com +2), others are between 10 and 14.
Surely other people have already played Nigrasaxa in 5e - I'd be happy to hear your experiences, concerning both the conversion as well as the adventure itself (it does feel a bit outdated and bare-bones).
I like the adventure and I’ve played it, GMing the middle chapter when our regular SG was out. My editorial advice is to change the name of the covenant, especially if you’re running for live players around a table where everyone will hear you say, and be expected to themselves say, “Nigrasaxa” multiple times every session. It just makes players uncomfortable. They feel like they’re being asked to say bad words, and we can avoid that whole problem by simply renaming the place, easy.
The word means Blackstone of course, which is a perfectly serviceable name, because the tower is literally made of black stone. So if you don’t want to change the name, simply refer to it always in translation. I always found Blackstone interesting because, beyond the obvious descriptive name, the name is presumably signaling the covenant as in opposition to Blackthorn. Otherwise, it seems weird that there’s two covenants in the same tribunal with such similar names.
It took me a while to understand what you wanted to convey. It's good advice for Americans! We'll be playing in German, so the name will probably be less of an issue.
I ran the first "chapter" of it for 5th edition as a one-shot, which went well, but we didn't use the player characters provided - I wanted to show off the flexibility of the chargen system (and had way too much time on my hands) so asked the novice players to give me character concepts for medieval wizards, which I then wrote up. Otherwise, I found the story works very well for 5th edition, but basically rewrote a lot of the stats from scratch. As you say, going with what feels right for the system is very much the way to go vs trying to figure out a conversion formula for everything
First time that I ran in the Rhine, I did that for Philipus Niger ex Flambeau which i turned into Black Peter/Schwarz Peter (while the dutch version has attracted a lot of negative attention, the Schwarz Peter that I grew up with a is chimney sweeping black cat). Now that I run again, I have Zwartpiet as the same chimney sweeping black cat, as the emissary of the urban Faerie court of Köln. Which made me go back to using Philipus Niger ex Flambeau in his original name, though since we play in German, the G isn't hard... and I still mostly refer to him as der Schawrz.
I had always read Nigrasaxa as "black sword", in reference to the Saxon Seax/Sax weapon.
