[@Deos Morran]
True, they are mentioned quite a bit, but it seemed like this was more of a story from the ranger side, if that makes sense. The only real time we're given much information outside of the lore section about seers is the The Other section, and that's only in the second paragraph.

And from the lore section, it seemed that beings with magical abilities were outlawed, etc. 

I'd gladly remake Matthias to be a seer, but I'd need a tad more info like Mataus is asking.