The Way Spellbooks Work

After writing up my new take on Read Magic house rules, it occurred to me that it affects my view of spellbooks as well. I've already mentioned that I see "spellbooks" as mostly being the charts and names and procedures for producing spell effects, rather than individual spell descriptions. In other words, an ephemeris, a table of correspondences, a list of sigils for the spirits and intelligences of the planets and constellations, a table of hours... that kind of thing. Magic-Users who lose their spellbooks don't lose any of their known spells: they just need to locate new copies of those charts and tables. Spellbooks might, however, include research notes for a new spell that is not common knowledge, so capturing a spellcaster's spellbooks might be useful. I do not follow the "casting spells from spellbooks" rule seen in some people's house rules or in Delving Deeper/The Fantasy Trip.

My new rules doesn't alter that basic take, but it does alter unique spells and acquiring spells a little.

Spell Research isn't as important

I had a rule before that PC spellcasters get the default list of 1st level spells and must research all other spells. Now, all they have to do is find a scroll or casting notes for that spell and use Read Magic. Spell research only applies to high- level spells (7th+) or creating unique spells.

Scrolls and casting notes become a way to trade spells

Casting notes cost half as much as a scroll, since they can only be used to learn a spell, not to actually cast it without memorizing it. Spellcasters can charge whatever they think they can get on the open market for a spell.

Spellbooks for known spell levels don't need to be identified

It's like Nethack: once you identify something, you will always recognize it. Any Magic-User can cast 1st level spells, so they will automatically recognize a 1st level spellbook. 4th level M-Us can't cast 3rd level spells, so they need to cast Read Magic to identify a 3rd level spellbook.

Unique spells can be learned from a spellbook mid-adventure

They can't be learned all at once, because of the 1d6 spell levels limitation I added. But if an M-U can cast 6th level spells and finds an enemy caster's spellbook with Unleash Kraken (unique 6th level spell) in it, that M-U could prep Unleash Kraken right there, right now. And if that M-U finds a scroll of Unleash Kraken later, that scroll is immediately recognized, without casting Read Magic.

Spellbooks will contain unique spells, if a caster has any

When researching a completely novel spell, the final casting notes are added to the caster's spellbook. Cost is included in as part of the research costs. If the researcher specifies beforehand, the casting notes can be in a separate manuscript and not the main spellbook. So an enemy caster who casts Unleash Kraken must have notes on that spell somewhere.

I can see some possible changes to amnesia and Feeblemind effects. I might have to cover that in a future post.