EldritchFire: Yes, I'm not arguing on the time spent actually *casting* the ritual. Just pointing out that there *is* preparation time required, even if we're advised to not spend player time dealing with that for small rituals. See the comments on time on page 261; I wouldn't allow thaumaturgy without at least a minute in preparation time, even if you manage to have all the right materials on your person already. (As far as that goes, we're advised to not spend player time on casting, either, unless there's some dramatic pressure - like zombies climbing up the hill towards your ritual site.)
Multiple taggable aspects is pretty clever, though, and I don't see any reason that couldn't be done with evocation if you've got enough power - though that'd get expensive, since you'd need to pay for multiple aspects (three shifts each) and enough duration to have a hope of using them all.
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CMEast:
The reason you stop at 6 shifts for a ritual is that, if it's over your lore, the rules are quite clear that you need to spend one or more scenes on prep work, and it's absolutely not something you can just toss off. (As opposed to something that you probably shouldn't be allowed to toss off, but that the rules aren't quite as clear on.) Now, if you're preparing for a fight in a siege situation, and you know when that fight's going to be, and you've got weeks to prepare for it... there's nothing stopping you from having a fifteen shift ritual running. Wizards are scary.
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How does a sponsor limit your potential to be a full wizard? You're paying refresh to be able to do something a normal wizard couldn't do, but, if you've got the refresh to spend, there's nothing stopping you from picking up "real" wizardry later. Even if you start with just sponsored magic and The Sight, well, that represents your non-standard approach to spellcasting, and when you've got two refresh to spend, you can pick up thaumaturgy or evocation.
(Yes, two refresh. Remember the cost break for sponsored magic: Even if your GM is playing it entirely by the book, with sponsored magic costing you four refresh, that goes down by one for each of thaumaturgy and evocation you pick up - essentially saying "I'm a normal wizard, now, but with this extra kind of magic I can do". Note that I wouldn't stack the normal cost break with the half price for limited scope I suggested above - two refresh to be able to use your magic in a way that nobody else can is probably about right.)
In fact, for a ten refresh game, you could fit in full wizard + sponsored magic right at the start.
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And on claws upgrading to channeling: We're probably going to have to agree to disagree here. The two are inherently different - as we've discovered from various attempts in this thread to make claws as an evocation.
Evocation costs mental stress. Takes an action to activate. Can be blocked by being in a grapple. Can be counterspelled, blocked by a circle, or otherwise magically shut down by someone who knows what they're doing.
Claws, by comparison, does not cost you anything. No mental stress. No action needed to activate - it's just there when you need it. It can't be counterspelled; it can't be shut down unless you choose to do that (as, say, a severe mental consequence or the like).
If anything, I'd see claws as, in this case, an upgrade from channeling; your initial fumbling attempts cost you mental stress on every hit and left you with splitting headaches after a hard fight. After some practice, you've got it down to a rote - something you can do, something that costs you, but you understand what the price is and know where your limits are. And eventually, when you've absolutely mastered the technique, it's simply internalized - no more stress, no more hesitation or complex and disruptable calling of power. Sure, that costs you an extra point of refresh, but it's still worth it - that's that much less mental damage you're going to take in an average fight; that's that much more you can use the power. With basic evocation, you've got maybe four to six hits before you have to rest (or take consequences); with claws you can take a few minutes and punch through a wall, or fight several opponents back to back without getting a migraine out of it.
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I expect you probably will end up struggling with this when trying to recreate other creature features or base physical powers; that's actually why I suggested sponsored magic, because it will handily cover all of those for you (as long as they're within the theme of your school of martial arts magic - for example, a combat style based on flowing movement and never letting the opponent get a solid hit in would probably not offer toughness powers as an option). And, again, spending the refresh to actually buy the power in question will be a stronger option than replicating it through spellcasting - no action to activate, no cost in mental stress, no way for someone to catch you with your spells down, etc. (The action to activate is a big one, actually - it may not seem like much when you're looking at just claws, but consider - say you take three exchanges to cast claws, and strength, and speed... by this point the fight might be over already, especially if you're facing guys with guns!)
The alternative here is to start using your enchanted item slots. There's a pretty good discussion
in this thread about using enchanted items for "always on" effects (and why "always on" in in-character terms can still have limited uses per game session).
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That all said, there is one analogy you can apply to possibly justify using an evocation to empower your fists with weapon 1 for a scene: Consider the guy who brings a concealed knife to a fight. He spends an action to draw (or maybe does it as a supplemental action, depending on how that concealed sheath is set up) - and poof! Weapon 1, for the scene, or until someone takes the dagger away (counters the spell). Were I a GM, I'd be rather wary of that train of thought... but I'd probably allow it as a rote that was tied to a focus item, thus replicating the physical constraints of the guy with the concealed knife. Also, this doesn't scale; you can't bring a concealed suit of full plate armor to a fight!