User blog comment:The man with no plan 24/New weekly SPECULATION blog./@comment-1185827-20170926093503

I don't think that access to magic is preconditioned on being marked by The Outsider. Certainly the mark makes magic easy, but we have seen people able to craft magical bonecharms with their own skill before. Perhaps what The Outsider bestows (and what was stripped from Corvo) is the ability to very easily access the powers of The Void.