Hello! Just discovered about Ars Magica, game looks wonderful. One thing caught my eye - the mechanica of Heron from Ancient Magic - and I was wondering if I were to have a "wonderous mechanica craftsman", would he be a Mythic Companion? Or Since the Mechanica of Heron requires The Gift, so would I instead build a character and give him The Gift, and then give him the Mechanica of Heron score (since The Gift allows a character to have one supernatural score without pre-requisites?) Or would it involve something else? I'm fine with not playing a mage, there's a few players and everyone's at the "lets play our dream characters" mood like kids in a toybox.
A craftsman of Mechanica needs to have The Gift, the Supernatural Virtue Mechanica of Heron and be Educated. For that they still can be a companion.
The thing to carefully imagine and check with your troupe is: Just how your character knows about Mechanica of Heron? Is he a scholar of old preserved in a regio? Or a Gifted young librarian fluent in Greek who found by troupe fiat an incorrupted text about the Mechanica?
Characters who have The Gift may start play with a single Supernatural Ability, without having to take any other Virtue [...] They may also take Virtues granting Supernatural Abilities if they wish to have more Abilities at character creation.
However, later on the same paragraph:
The ability to cast Hermetic magic is the single supernatural ability possessed by Hermetic magi in virtue of The Gift; again, they may take more Supernatural Ability Virtues if they wish.
So if you want to also be able to do standard hermetic magic, yeah, you will need both The Gift AND Mechanica of Heron. But if you only wants Mechanica, with no hermetic magic, than The Gift is enough.
If you are starting at Ars now, I'd suggest you to lean towards "simpler" characters. Ars is, by nature, a complex game. No need to increase the complexity even more right from the start.
But I get the appeal to make "the dream character".
While in theory Mechanica is Ancient Magic, if you troupe is ok with that, consider making an Ex Misc character who is a survivor of Heron's tradition. Ex Misc magi get a free Major non-Hermetic Virtue, and Mechanica of Heron qualifies for that. Thematic Major Hermetic flaws could be Waster of Vis (you never learnt properly how to use this thing, since Mechanica doesn't require it) or Unstructured Caster (focusing more on Mechanica than hermetic magic resulting in a poor grasp of formulaic spells). These are just suggestions, of course.
Normally, Mechanica of Heron is lost magic. Which means learning it is normally the culmination of a few years of campaign that is done with a high magic theory character rather than something you start with at character creation. Your troupe may choose to ignore it, however, and with the "lets play our dream characters" mindset, that may be very appropriate indeed;
If your troupe decides to ignore it, the easiest is the pay the virtue, yes;
A Mythic Companion would be a replacement magus character. Mythic Companions don't have the gift, it's normally an either you're a magi, or you're a mythic companion. Which means you either play an hermetic magi that has the hermetic versions (post-integration), or you play a hedge wizard that has the supernatural virtue. what the rest of that tradition would look like is up in the air, I recommend looking up Hedge Magic Revised. Learned Magicians and Elementalists (because of the type of powers that can be embedded) are the traditions that would make most sense to add Mechanica to, if it still exists, if you want to play a non-hermetic magi.
Rafael's ex Misc suggestion, with the supernatural rather than the hermetic virtue tradition, makes the most sense within the Order unless your troupe wants the virtue to have been fully integrated.
