Spellcasting and interruption.

[Valmorian]

I've noticed from the BFRPG core rules that it appears any attack or required save on a caster's initiative number will cause them to lose the spell they are casting.

This makes me wonder if initiative numbers are supposed to be hidden or revealed for NPC's/Monsters. If hidden, a caster would have no idea if they are going to be able to cast their spell and if revealed then no caster would even try on a number that matches the time monsters would take their turn.

Furthermore, how do you generally handle intentions on matched Initiative numbers? If the GM goes first, then no caster will attempt to cast, but if players go first then they have to guess if the GM will attack them or not.

All these things make a big difference, since merely the attempt to attack will foil a spell it makes spellcasting a very difficult thing to pull off!

As a bonus note: The Draugr monster in the field guide indicates that casters will lose the spell they are casting if they fail a saving throw vs. the Draugr's icy breath attack, but given RAW, wouldn't they lose it anyway? (Failed saves cause spell loss as per the main book).

[Christopholis]

The exception in that paragraph seems contradictory too.

At first it says both spells can go if on the same initiative count. (Which begs a different question about why simultaneous spells don't hinder each other, but spells lose out to simultaneous frog spit and kobold spears.)

However, it goes on to say the only way to interrupt is to delay until just before. If just before means same initiative, then the earlier part says it doesn't interrupt. If just before mean one initiative count earlier, then it doesn't trigger the interrupt rule anyway.

And it's only when vs. each other. So, you and I cast at each other, both spells go off. You cast at me, I cast at Ted, and Ted casts at you, no spells go off?

I assume it is for cinematic magic shootouts, but it gets weird when you consider there's no rule for who declares first. If I declare first and opt for a spell, you can cast at me knowing your spell will go off. If I declare first and you opt for a dagger throw, my spell fizzles. Or I declare first but not at you, then you cast at me, only my spell fizzles? Or as you said above, if you declare first and make any attack roll, I just won't cast because it would be pointless. I'll just wait 1 initiative then cast uninterrupted with your dagger sticking out of my forehead.

I would humbly submit the problem is it's not "successful attack" and "failed save." I get the "but you had to dodge and that breaks your concentration" part, but is that really worth allowing a guy to get mutilated then cast, or disrupting a lich's high level spell because I dropped any spell at all on him on his initiative?

Outside of spellcasting, since initiative is only a d6+dex, doesn't this "who declares first" thing come up a lot anyway?

[Solomoriah]

No one "declares" what they are going to do, they declare what they are doing.

You're making this a bit too complicated, honestly.

Assume that two wizards, let's say Prentice and Coldarius, are fighting. Prentice has the initiative, and knows it, and wants not only to cast a spell but to interrupt Coldarius. He can attempt this because he has the higher initiative... if they rolled simultaneous, he could not. But he does have to wait until his opponent can act before casting.

Coldarius, a ruthless and clever man, knows his opponent has the initiative, and sees that he is waiting... obviously, Prentice means to interrupt his casting. Coldarius then chooses to wait also, leaving them in a standoff. He can wait until the end of the round if he likes, and it's possible for the round to end with neither man casting a spell. Or he can fake it, raising his hands and pretending to begin a spell in hopes of fooling Prentice. If Prentice is a PC, I'd think up some kind of roll for him to make to detect the fakery (probably an Intelligence ability roll).

NOW let's consider the more common case. Prentice stands behind a couple of meat shields, with a cleric behind him and a thief at his side, and down the dungeon corridor stands Coldarius behind ranks of zombies. They are no longer dueling, it's a normal combat. In the first round, Prentice gets a better initiative than Coldarius, and decides to use a magic missile not only to injure his opponent but to interrupt him. Prentice holds his initiative, knowing that his opponent's attention isn't fully on him; at this point I'd make some kind of roll for the NPC Coldarius (probably an Intelligence ability roll) to discover that the fellow hiding behind the half-ogre is plotting something. If Coldarius goes forward with his own casting, unaware of Prentice, then Prentice successfully, automatically interrupts Coldarius, spoiling his spell.

This is Old School. You can't just read the rules. You have to interpret them in light of the current situation in your game, and be prepared to make rulings as to how they are applied in specific situations.