Howdy. Welcome to the boards and game.
Lycanthropy can, as far as I can tell, be caused by any Realm, and be due to any number of reasons. You need to come up with a reason (and Realm) that will give a fun adventure for the player and group (and you) to game through. I know that's not too much of a help, but really it depends so much on your preferences, there is no single reply. Some wild ideas -
- His state is a Magical situation, not a curse. He can "overcome" it by discovering his inner animal spirit and coming to live in harmony with it, perhaps with the aid of a Bjornaer magus (joining the House), or perhaps by discovering the ancient race of minotaurs in the Magic Realm, his ancestors, and convincing the Minotaur King to release him from the curse.
- His lycanthropy is a result of an Infernal curse. He can reverse it by a Divine quest, if he beseeches the right saint and quests to find the right angel (which will probably require further things of him). Or he can force Hell to rescind it by force, through climbing up Hell's hierarchy to find the demon who cursed him and make him undo the curse. Or he can bargain with hell to lift his curse in exchange for certain... favors. Probably very few, easy favors - after all, once the bargain is made, the demons have leverage on him ("You wouldn't want this little piece of evidence of our past bargain reach Quaesitor Lucretius, now would you?").
- It could be a faerie curse, perhaps granted by the ancient goddess Selene, goddess of the moon and madness. He could lift the curse by visitng her in faerie and becoming her servant. Or he could lift it by freeing her from imprisonment at the hands of the Prince of Darkness on the night of an eclipse. Or perhaps the curse was by a more minor faerie, which could be killed to lift the curse, or his name discovered and said three times.
- It could be a Divine curse. In which case, the only way to lift the curse would be to repent and worship god with all one's heart, probably including a Divine quest of some kind.
Really, the statistics and details of the curse are up to you. There is no universal solution.
The wooden leg can be created in several ways. Just follow the normal rules for creating a magical item - it can be a lesser enchanted device, an invested device, or a charged item. I'd suggest the player make it an invested device and turn it into his Talisman, just because it's a cool concept, but that's up to him.
Rules for automata are provided in the Houses of Hermes: Mystery Cults book, along with other Inner Mysteries of the Verditius. Similar (I believe better) rules are provided in Ancient Magic, for Heron's Automata.
It is also possible to make such devices using normal Hermetic magic, however. I personally prefer saying that to do that, you need to imbue the machine with an animated spirit, which requires a proper Rego effect to bind a spirit to it (either with normal magic, or with the rules given in the 5th edition The Mysteries regarding binding spirits) - but some say that's not needed, as a Creo X effect can create a Cunning spirit. At any rate, once you have the spirit you can create another effect to read its mind (Intellego Animal or Intellego Mentem), and then invest further effects to trigger when the spirit thinks the command word or so on. The result is that you need to create the machine as an invested device with several effects, but it is done without any Mysteries (unless you use the Spirit Magic mysteries in The Mysteries).
I don't really remember the 4th edition rules for automata, but I remember not liking them. Magic hasn't changed that much, though; if you want to adapt the old rules, I can't imagine why you can't just take them and use them pretty much as-is.
, both english and Ars Magica.
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