Spell suggestions

Let's be honest: some spells suck. Here's how I think we could improve them.

Vermin: increasing decay rates for food is a terrible idea, for a number of reasons. For one, decay is linked to food stockpiling levels, which means that this spell barely does anything against people you're trying to starve. In second place, 5% extra decay isn't a lot of food. It takes 10 ticks to consume 46% of the target's food (actually more, but I don't feel like doing the math here) - which is what you get with a single rob the granaries, one of the easiest ops to pull. Vermin isn't exactly a hard spell, but it does consume runes - plus it's on halflings, who don't have any magic bonuses, and faeries, who have much better spells to cast.

So how to improve it? I have three suggestions:

1. Increase decay to 10% across the board. This one is pretty straightforward.
2. Increase rune decay, too. Unlike food stockpiling, rune stockpiles are actually fairly dangerous, and robbing towers isn't as effective in removing them.
3. Make people with vermin more susceptible to plague. I think this would encourage interplay with other races (undead, too) and would make vermin a lot more useful in certain situations. Plus, y'know, vermin have traditionally carried the plague, so it makes sense in a way?

Fool's Gold: this one is easily the weakest heretic spell. I think the main issue with this spell is that it's just a poor man's Rob the Vaults, trading a little bit of effectiveness for costing runes and giving you nothing in return. Outside of a very niche situation (i.e. a rogue stockpiling gold) it has no use whatsoever.
And sure, you could up its effectiveness (so instead of 25% of the target's gold it takes away 33%, or 50%, or whatever) - but I think that would still make it feel like a second-rate Rob the Vaults. Spells should be at least somewhat different from thievery ops, IMO. So my proposal is: instead of calculating FG's to take away a percentage of the target's gold stockpile, change the formula to something linked to the target's net worth. For example, if your province is worth 200,000 gc, make it take away 50,000 gc.

Why? Because, in this way, if they have less than (NW/4) gc, they end up with zero gc. No other spell or op can instantly leave you with zero of anything. This would make it a very good spell, with correct timing, to gold-starve people, thus increasing its strategic value. It might even need to be nerfed somewhat (so it takes away 1/10th of your NW in gc, instead of 25%, for example), making it a situational spell not unlike the other Heretic spells.

Crystal Ball/Eye/whatever: right. So. I know this one was taken out and for good reason - intel belongs to thievery, blah blah. However, there is one piece of information that really fits into magic and you could bring back this spell to give you: what spells affect a province. Make it cost 2% mana and give you a list of all magic auras affecting a province.

Magic Ward, Barrier of Integrity: I just think these were fun spells and should come back.

My two cents:

I like your suggestions. For Vermin:
1. If it was kept as a food reduction spell, I would use the Networth based damage idea you posted for Fool's Gold. And for anyone quick to complain about Food not having a NW, it has an aid value.
2. What I like better is to completely retool it into a sustained spell and give it Blizzard's -10% BE and your idea of increased susceptibility to the plague. This gives it an effect against those provinces that are immune to the plague so you can't ignore the spell at race/personality selection. I would make Blizzard an increased attack time spell - add 10% to a province's attack time. Maybe stronger; because with the 7 hour attack windows all it really does is limit the use of the + hours options.

For Fool's Gold: I like your idea of NW based damage, however I would change it from destroying the gold stockpile to raising training rates. This would make it effective against provinces that are gaining acres to slow their growth, however not a must-cast on everyone.

For the rest, I don't really have an opinion.