I do like how the system really plumbed the depths of 3rd Edition for class inspiration. There are a lot of obscure mechanics that I haven't seen in a good long while (truename magic, spirit shamanism, etc).
By my reading, we would have to have someone with a basic ability that heals wounds in order for Giuseppe to brew a potion for healing. I may not be understanding the system fully, though. Yeah, the whole vitality = character capability = initial HP pool seems difficult, but I am looking forward to seeing how it plays.
It's possible that the Order of Shadow may make spellcasters and others available for that purpose, I guess. It's weird though, I would think this would be limited to Magic abilities, but there are example potions where the inputs are mundane abilities.You place an ability that you or an adjacent
ally knows into a potion, salve, oil, pill or similar mix that delivers a
single-use effect to a creature or object.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.