Can you combine Fast Study and Psychic Asylum to fill all of your open spell slots as an immediate action?
Fast Study allows a Wizard to fill all of their spell slots in 15 minutes. Psychic Asylum is a 6th level immediate action spell that freezes external time and give you 15 minutes in a mental mindscape with perfect recall of any text you've read in the last level/week. Like your spellbook.
It also specifically says "If you're able to prepare spells, you can use the time to prepare a single spell." RAW that's clear, it's trying to curtail the normal limit of up to 1/4 of your spells limitation that normally applies to 15 minutes, but I also imagine Fast Study wasn't considered.
I'm thinking a limit of 4 spells (the 1 hour to 15 minutes multiplier rather than the 15 minutes to 1 minute multiplier) would be a reasonable compromise. What are other thoughts?
I am thinking this is a "specific trumps general" situation, where given that the spell specifically says one spell, you're stuck with one spell. Even though Fast Study may or may not have been directly contemplated in the drafting, the specific wording would govern over the general application of Fast Study.
Having said that, a GM could always house rule the situation in the manner your described, if he or she felt it was balanced.
Also, I would think this should get shifted to the Rules Questions forum.
The RAW is clear, so it's not really a rules question.
If you're able to prepare spells, you can use the time to prepare a single spell.
RAW actually is quite clear; it says one spell. It doesn't say "use the time to prepare spells", it says "a single spell".
A wizard shouldn't be able to spend a swift action to prepare 15 spells, as the closest comparable ability only allows one spell as a standard once per day.
The RAW is clear, so it's not really a rules question.
Fair enough. So your question is whether it would be a sensible house rule to apply the two things in the manner you've suggested?
If so, I think it is probably unbalanced. For the cost of a single feat/discovery and a spell (though a higher level one to be fair), the character gains a massive amount of flexibility. Not only would the character be able to leave 4 slots open and then fill them all at once, as an immediate action, but it also sounds like he or she wouldn't even need to reference a spellbook.
My feeling is that the drafters put the spell limitation in place for a reason, probably to prevent this exact situation.
I accept that.
However, it seems there's nothing in this spell to prevent a Magaambyan Arcanist PrC from using their (3rd level) Intoned Recollection ability to swap out Int modifier spells as an immediate action in combat. A great option for that prestige class. At best you can limit their ability to prepare from a spellbook to one spell, but you shouldn't be able to stop them from using their Spell Mastery spells in open slots.
Hmm.. at first I was agreeing that, as a house rule, 4 would be fine. But The Steel Refrain makes good points, and I realized the real question is, how much longer is 1 hour than 15 minutes?
In game terms, it's decidedly not 4 times as long. If you have 15 minutes to spend, you probably have an hour. About the only effect would be on 10 min/level spells (or min/level at very high levels).
That said, there should probably be *some* synergy - so perhaps two spells instead of one.
I personally would still limit it to one spell (RAW). More time to do other things is fairly strong (you can, for example, look up information you found earlier on whatever you are fighting, which could give important information you missed earlier), in addition to giving you time to run out the clock on some spells, and usually one spell is enough to flip an entire encounter on its end, especially if you can cherry pick the best for the situation.
a mental mindscape with perfect recall of any text you've read in the last level/week. Like your spellbook.
What makes you think a spellbook contains nothing but text?
You also remember every conversation you heard and image you saw for level/week. Trust me, you're covered, that's why they directly acknowledged and limited the spell prep issue. Theoretically they could be talking about only divine prepared casters who don't have this spell on their list, but no.