I wonder... what if Viserys tried to summon Yrael or Mereth?
One of either fizzling or Bad Things Happen. The first thing Viserys did was try to Bloodwish a Plane Shift, and depending on if a level 18 Viserys would have taken the spell, he may have gone for a full bore Transport Travellers Wish. Neither will have worked, and the latter would be a reason for Mab noticing him. As to where his multiverse is, well that's somewhat obvious. According to Mab, and she was being truthful in this, he bears energy from beyond the Gates. Some of that is his magic, the rest is a sort of fading signature of somone who was blasted across realities.
Further, I would suggest that people don't assume conservation of capabilities where it comes to Viserys' magic in the Dresdenverse. In general, yes, much of what he can do will be powerful and OCP inducing on some levels to a merely 'human' wizard. Equally though, there are DF things that will surprise him.
As to magic and culture shock, the largest problem he has is actually one of not understanding the universe's metaphysics, and they hold primacy in this case. Although Viserys has high stats and massive knowledge skills, he's running under equally huge penalties right now because the entire world around him is 'wrong'. Cultural Adaptation is unlikely to fill that gap and is also only a temporary measure - it's limited duration, after all. There's also the question of
which culture.
On the matter of the Laws of Magic, people are quite correct that they only apply to mortals and Viserys is a Dragon. The problem here comes in proving that. He's using his human form and is continuously under a Mind Blank effect, that has connotations. I'm still not quite sure how Mab knows that he
is a dragon, actually; probably Fae bullshit of some sort though.
The far more likely conflict point is how Viserys will react to how the Laws of Magic function and are applied retroactively and regardless of ignorance, especially when the Doom of Damocles
does work. It's just that murder is 'easier'. There isn't much nuance there, and it's one of the few easily discoverable things that could set Viserys off on a cold rage. He'd be polite, no doubt, but once he gets the truth of the matter out of people it's not going to be pleasant. Powerful beings have a way of bending reality through their presence in the Dresdenverse, sympathetic connections to the Nevernever caused by their nature and etc. Viserys is, whilst not on the level of the Queens, certainly powerful enough to cause this. The results of that are going to be fun.
Edit: also he's broken three(ish) Laws since arriving, and that's what matters. I'm not counting everything that came before he was reality whacked.
?
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