My top choice would be:
Transmigrate: 1)Movement from one site to another, which may entail the crossing of some usually limiting membrane or barrier 2)be born anew in another body after death
but depending on the attitude towards the process on the magical side (ie is being on that side considered innately better and/or whether the jump considered going up, down, or just sideways?
"Make the Jump"
Exodus
Ascend
Transcend
Awaken
Fall
Shadowwrap
These are all very good ideas for one extra reason: different groups in the Dark World may see the transition differently. Some who think that magic-users are 'the next stage in human evolution' or some other Theosophist claptrap could use terms that imply emerging from a coccoon or some other one-way transition, like 'ascending' or 'awakening' because who could
ever think that the mundane world was better than the supernatural? Other groups who have learned through bitter experience that magic can cut both ways might use terms like 'fall' or 'banished' that imply a loss of innocence or other unpleasant transition and might even hold a secret belief that a magic user can somehow abandon their powers and return to being a fully mundane human.
"If I had my time over again, I'd be someone happy and distant and
small. Live in a hole in the ground, maybe.
Never to get involved in the affairs of the great, and the powerful.
Never to discover the joy of the art." - Neil Gaiman, "The Books Of Magic"
