What is the threshold strength of the sunrise?

Question

Mechanically, the Dresdenverse sunrise is a threshold that sweeps across the world (instead of a creature or spell trying to cross the threshold):

Thresholds can even be conceptual: the transition from night to day has a weakening effect on magic precisely because it is a sort of threshold. (YS230)

Looking at the modes of a threshold (YS230-231), the sunrise acts as a suppressor (reducing effects by a number of shifts equal to the threshold's strength) and as a source of harm (attacking vulnerable creatures with the threshold's strength).

So what is the sunrise's threshold strength? The Dresdenverse sunrise is a powerful symbol of fire's cleansing and purifying qualities, as well as an ancient sign of hope and renewal: the man clutching his pointy stick beside a campfire has survived another night outside the bellies of the prowling beasts.

The sunrise's attack effect is portrayed as universally and automagically destroying ghosts, certain vampire types, and ectoplasmic constructs --up to and often including those with "plot" levels of power. On the other hand, although the suppression effect trashes most unprotected spells it's possible to design spells strong enough to weather a sunrise simply by using shifts to increase duration as normal.

How can we reconcile this apparent dichotomy of strength? The sunrise should qualify as a Catch for most if not all of the creatures it is able to attack; would that be enough to eradicate a summoned demon but let a spell survive a sunrise with just one extra shift? If so, that still leaves the question of its numerical strength. Or does the GM simply rule that the sunrise functions at the power of plot discretion?

If I'm barking up the wrong tree entirely about how the sunrise works mechanically, I'd happily accept an answer telling why and how I should be modeling it differently.

Answer 1

I think you might be over thinking it. Dresden Files and Fate aren't big on accounting and precise timekeeping, so it's kind of a wing it situation. To summarize the bit on Duration and Enhanced Evocation on YS265-266, when sunrise happens:

1. Any ongoing evocations end. That's probably not super important, since they're extremely short duration anyway. I would only expect this to happen as a GM fiat kind of thing or maybe a player spending a fate point to take advantage of a "Dawn is imminent" aspect that exists on the scene.

2. Any thaumaturgy spell that didn't have enough extra shifts of complexity to bring its duration to longer than "a day" ends. Don't worry about anything like "Well this spell was a 8 shift ward yesterday, with sunrise it's a 6 shift ward today", there's AFAIK no mechanics for that. If you're GMing and that sounds fun to you (maybe as a way to temporarily gate access to things for plot reasons?) go for it, but just do whatever will serve the story and make things interesting.

Now for sunrise as a suppressor and source of harm... I think you're basically forced to wing it and use your best judgement. Anybody that has a "Catch" related to sunlight obviously loses their toughness and recovery powers while exposed to sunlight. I don't think there's any mechanical support for taking an X stress hit for being exposed to something you're vulnerable to (check Our Story for the individual critter descriptions?), so it's again going to be a plot-device, it's-as-strong-as-serves-the-story kind of thing. Expect nameless vampire mooks to go "poof" when dawn breaks and major vampire antagonists to live or die based on what act of the story you're up to. Anything that can "poof" without being removed from the story (like ghosts, demons, etc) probably should poof. Mechanically, this is probably a compel on their high concept.

It's kind of important to remember that Dresden Files is some guy writing fiction with the primary concern of telling a good story. The DFRPG is a bunch of people trying to cobble and all the things that happened in the fiction into as coherent a set of guidelines as they could manage. It generally works pretty well, but it will leave a lot of stuff up to the discretion of everybody at the table.

Answer 2

Well going off of the example in the "Potions" section, it says that the sunlight in a hanky is a weapon: 3. Just going off that I would make it a lvl 3 threshold, or more realistically because the things affected don't have to push their way into sunlight, a lvl 0 threshold with a 3 shift fire evocation landmine that only targets specific monsters, but that is just my opinion. However the sunlight in a hanky could well be weaker, like a watered down version of the sunrise.

In the books the sunrise eventually breaks down all spells, which makes sense because eventually it would wear them down using the breaking through thresholds rules. A sustained attack at 3 shifts might not do it mechanically, but realistically, but thats not accounting for time. Lets say the sun can hit your wards for a minimum of 3 hrs a day. If a turn lasts 5 minutes (way longer than a turn imo), that means the sun is attacking your wards 12 times an hour, for 36 attacks minimum using 5 minute turns. EVERY DAY. So that is 108 shifts of power being thrown at your wards.

Also the sunrise has the power to completely dissolve ghosts, if I am not mistaken, provided they aren't protected somehow. This means it would have to be monumental, so much so that not even taking all of the possible consequences would let you survive, but something as simple as a bachelors threshold can protect you. That suggests that the sunrise is a special type of energy affecting different entities in different ways, or that our very bodies generate protection for our souls, although hiding underground or in some place the sun never sees should work as well.

As I said this is merely my take on the situation. In reality it comes down to your GM's discretion, like so much else in this game.