White court vampire catches are super secret from how I interpret it.  And their catch is +0 for how easy it is to research.  Didn't Harry learn the Raith Catch from Thomas himself?

I don't have my books but they have base requirements for discovering catches and isn't 'intimate knowledge' a basis for a +0 catch?

If that's the case, then I don't think a random Lore roll would fit the bill unless you have an aspect to represent that kind of knowledge.

I suppose you could set a base difficulty, like legendary and each +1 on the catch represents an aspect (or a -2 to the difficulty)

I'd put BCV around +2 since that knowledge is available on the internet and I think they rate the internet at Fair.  (Once again, I don't have my books).  It's probably also available as a scholarship roll as well as a lore roll given stokers Dracula is everywhere.

Supernatural speed reads "You're able to move far faster than the eye can see -- or at least so fast that what's seen is only a blur..."  From what other people are replying, it looks like I need to cut back on what he can do in terms of speed.  Also, due to the reading of the rules, I didn't allow the driver to make a dodge role with his driving skill because I assumed he didn't have time to get out of the way.

What about a Weapon:7 sleep spell from an accomplished biomancer wizard?

This reminds me of my NON LETHAL TAKE-OUT GAME

It's part of the "mid session power upgrades" rules. There's a yellow box on page 92 in Your Story called "Temporary Powers".

Reading through it again, it even talks about that the player can owe the GM compels, if he doesn't have enough to pay for the temporary upgrades. Wrapping those into a theme of sponsor debt would therefor work rather nicely.

Seems easy to me: the Black Court are basically corpses re-animated with some kind of specific, strange, powerful necromancy. The Master vampires impart a portion of that energy into a corpse to create a new Blampire, which then grows in strength as it feeds and ages. That means there is the same kind of link between the new Blampire and its creator as there is between a mother and daughter's blood. So you create that link between the two and follow it. As far as following that link back, the first idea to pop into my head is to cut off one of the Blampire's fingers and use it as a compass-point.

This is in the Using Help section of the Thaumaturgy chapter. If a second spellcaster is capable of casting the spell--i.e. has Thaumaturgy or an appropriately-themed Ritual spell--then they can add "controlled shifts of power"--aka, you each get to summon and control some number of shifts on your own. Harry says you can't do this with more than 13 wizards, "because it just works that way" or somesuch excuse." Anyone help absorb Backlash as stress/Consequences.