There's a bit more about thresholds in White Night.  When Harry makes contact with the minor practitioners there's bit of a debate over whether to invite him in or make him leave his power at the door.

Richard

True.  And I believe another option was to simply wreck the threshold/ward, which was woefully weak by his standards, but this would have been understandably viewed as a hostile act.

If you need rules for it, you could probably call it a ritual and adapt the rules for conjuring.  By default, Holy Water is pretty simple stuff (no moving parts and such, so perhaps the base difficulty would be a mere 1.  That would be for, say, a vial of holy water.  Then make up a size chart similar to the time charts, perhaps something like this:

  vial - pint - gallon - basin - tub - spa - pool

Each step up the chart requires an extra shift.  Base time might be the length of a typical mass or service, and the time could be reduced by paying shifts.  Translate the preparation options for Thaumaturgy into more religeous trappings, such as holy places instead of ley lines, blessed fonts in place of a ritual circle, meditating on the scriptures instead of spell library research, etc.

The rolls would certainly require Conviction and possibly Scolarship or Lore, and only those with the proper Template and/or True Faith powers would be capable of creating it.  There might even be room for a stunt adding an 'expertise with holy rituals' trapping to Scolarship.

A couple of things mentioned about DFRPG Fae:

YS10: "fae literally cannot step outside their natures or break oaths"
YS75: "If taking on another ability reduces your character’s refresh to zero or otherwise fulfills all the “musts” of a faerie of the appropriate type, the changeling’s Choice is made and he becomes a full faerie, never mortal again, and now fully subject to the will of the Faerie Courts."

These quotes make it clear that Faeries are *intended* to be non-playable as characters.  On the other hand:

YS74: "Eventually, too much transformation will lead to an inability to retain a grip on mortality, and the character slips into faerie (often becoming an NPC as his power costs rise to exceed his refresh)."

The word 'often' implies the possibility that becoming a Fae need not relegate the character to NPC-dom, so long as positive refresh remains.

I think the bottom line is this: in "Harry's World" a Fae cannot be a player, because by definition a Fae's will is subsumed by the Court.  But you will be playing out Your Story, so it's up to you group and your GM to decide.  And it's an interesting concept, so why not?

In Grave Peril, when Michael seems surprised that Harry already knows Father Forthill, Harry mentions that he once asked Forthill to bless a barrel of holy water.  He then says "Talk about your surprised ghouls".

See OW58 (the text for Ghouls, not the statblock):

Weaknesses: Affected by holy water.
Unwavering inability to control their appetites
for long. Most are kind of dumb.

Regarding Ghouls and thresholds, I infer the following from the rules (though there are no specific rules for ghouls and thresholds in particular):

* A threshold acts as a block against supernatural creatures.  As this affects Wizards, I imagine it would affect Ghouls, as well.  (Note that this makes entering more difficult, but not impossible.)
* A threshold suppresses some supernatural abilities.  All affected supernatural abilities lose shifts of effectiveness.  Since the books indicate that thresholds provide defense against ghouls, I would assume that their supernatural abilities would be affected.  How much?  Hard to say, though as a first guess I would say that two points of threshold would remove Inhuman Strength and Speed and reduce Supernatural Recovery to Inhuman; four points of threshold would eliminate Recovery, too.  Most likely ghouls would be unable to feed while affected, though they would still be subjected to the negative effects of hunger, etc.  Oh, and any threshold at all would likely nix Human Guise for the duration.
* Some creatures (creatures of spirit) are entirely supernatural in nature and can't cross thresholds at all.  I don't think ghouls would qualify for this, however, as they are nominally semi-human.

Note that holy places have a default threshold strength of 3, but could be higher, especially if inhabited by a person of True Faith (Bless This House would likely increase this to 5).

That said, it isn't entirely clear to me whether you intended your version of Mother Theresa to be a truly holy person who was also a ghoul, or a evil ghoul impersonating a holy person.  Your references to the Sabbat lead me to believe the latter.  In this case, consider that while holy places have thresholds ... not all building that are used as a 'church' are necessarily automatically a holy place.  An evil ghoul might work out of a building that is 'impersonating' a church without actually being one, and therefore without having a threshold.  So the evil Mother Theresa would have no threshold-related problems.  However, the 'church' would also likely have some fairly foul aspects associated with it (Mother Theresa's Cathedral, Where The Other White Meat Is Always Fresh!), which would likely be palpable in some ways to even mere mortals.  And, of course, she'd have severe trouble entering actual holy places.

Of course, these are just my takes on the question.

Regarding the question of "Does using a magic weapon to kill a human count as a 1st Law violation", I think the fact that Wardens routinely use magic swords to kill without breaking the Law to be proof positive that it doesn't -- or at least doesn't always.  I think that I would rule that it depends on the type of magic used.  Passive magic (like a Warden's blade) does not require the Will of the wielder to operate, and therefore is not a 1st Law violation.  Active magic, such as casting a fireball from an enchanted item does require the Will of the wielder to perform (Discipline roll required).

Hm.  I'm trying to recall whether Harry uses his kinetic rings against humans, and if he does so with care when he does.  I can think of all sorts of occasions in which he uses multi-ring salvos against monsters or inanimate objects, can anyone cite a case where he lays a major smack-down on a human, or considers whether or not he should?

I do feel the second interpretation (power loss as alternate consequences) seems more in line with the system, but the problem with the second interpretation is that it seems too lenient.  It will lead to situations in which consequences only occur if more than a couple of scenes result in failed discipline rolls in a row.  (Because the rules also state that the hunger track is cleared by a subsequent successful FD/discipline check at the end of a scene.)  So, for example, if I had a semi-decent discipline (3 box hunger track) I could take up to three failures, then deliberate make light use of my powers in the fourth scene (possibly a non-combat scene?) to wipe the hunger track.  This also makes little sense, which leads me to the conclusion that this mechanic needs house rules.

Here's a first stab.  My attempt here is to make hunger management something the player has to deal with, while not making it crippling to the point of making the character unplayable.

Leave the "Hunger Is Stressful" section as is.

Change the "Limited Reserves" section as follows:

At the end of any scene in which you have exerted your affected powers, you must check to see if you experience feeding failure. This manifests as an attack with a strength equal to the total refresh cost of the abilities you used; you roll Discipline to defend. For example, if you used Inhuman Strength and Inhuman Toughness in the scene, that’s a total of 4 refresh, so you’d be rolling your Discipline to meet or beat a target of 4.  (Note that cost reductions such as The Catch do not reduce the refresh value of powers for purposes of Feeding Failure tests.)
* If you succeed, you avoid the worst ravages of your hunger.  Even so, you suffer a 1 stress hit to your hunger stress track.
* If you fail, you take hunger stress as though you’d suffered an attack.
* In either case, If you have physical or mental consequence slots open, you may use them to buy off the stress as per the normal rules (page 203). If you cannot or do not wish to spare consequences, then you may choose to lose access to a number of your powers, up to a refresh cost equal to the amount of stress taken. Reduce the stress taken by one for each refresh point of power sacrificed. These options can be combined however you choose.
* If there is sufficent stress remaining after any reductions from consequences or power loss to go past the end of your hunger track, then you are taken out by a feeding failure (resulting in complete incapacitation, extreme emaciation, and other nasty fates).

Change the "Failure Recovery" section as follows:

To recover from hunger consequences, regain lost powers, or remove hunger stress, you must feed as appropriate to your dependency.
* Any time you trigger your feeding power (ex: Blood Drinker or Emotional Vampire) while inflicting a consequence on the victim, you may remove one point of stress from your hunger track in addition to any other effects of the power.
* If you opt out of a scene entirely in order to feed, then you may make a feeding check using an appropriate ability against a difficulty determined by the GM.  (For example, A WCV that opts out of a scene in order to feed at a rave might test with Presence or Deceit against a mediocre difficulty, whereas a RCV who finds his reserves depleted in the middle of a wilderness might have a much harder time of it.)  If this check is successful, then all stress is removed from your hunger track and one point of lost power is recovered per shift generated.  Alternatively, some or all shifts can be used to recover from or reduce the severity of hunger-induced consequences regardless of the usual recovery time at the rate of one shift per shift worth of consequence.  For example, a severe consequence could be downgraded to a mild consequence if four shifts are allocated to it.
* You can regain all of your lost abilities (hunger-caused stress, power loss, and consequences) in one scene if you feed so forcefully as to kill a victim outright.

Any thoughts?  Some features of these house rules:
* A character with feeding dependency could probably hold off for several fights, so long as some care is taken with over-use of powers.  A high discipline is of considerable value here.
* With a 1-stress minimum (similar to the minimum stress caused by casting a spell), even the most disciplined vamps will deplete their reserves eventually if no attempt is made to feed.  Using feeding powers (appropriately) in combats can allow for some hunger mitigation.
* Opting out of a single scene has a reasonable chance of allowing full recovery from all but the worst hunger attacks or sustained abstinence.  This is especially true if the player comes up with a good feeding plan, thus minimizing the difficulty.

Some possible options:
* When determining the strength of the hunger attack, add one to the attack strength for each box already marked off on your hunger track (so if your first and third boxes had been previously marked off in the preceeding example, you would add +2 to the strength of the attack for a total attack strength of 6).
* It may be that the ability to feed during a normal scene is too powerful.  If so, this can be altered so that the character may either remove one stress box or one point of stress each time they take out (without killing) a victim using a feeding power.  Taking out a victim but avoiding killing them while feeding might require a discipline check, with a failed check being rather problematic for a RCV.