How can I increase Spells per Day for my Inquisitor most effectively?

Question

So, I'm making an Inquisitor in a PF game, and since I'll be taking the Spellhammer archetype I was wondering how I could increase my spells per day so I have more slots to spend on Spelldrive. I was suggested a few methods to help spellcasting such as Pearls of Power and Runestones of Power. However, while these are useful for preventing me from actually using spell slots to casting spells if needed, I still don't know if there are any ways to increase my actual spell slots aside from leveling, let alone which of those are good.

I am looking for any effective solution here, be it from gear, feats, traits, or even multi-/prestige classing.

3.0/3.5 material is also occasionally allowed upon request, and BoVD is open except Ur-Priest.

Answer 1

Simplest answer is Extra Spell Slots feat. It is not quite on the list of your allowed resources, but it is published by Super Genius Games, the same publisher that created Spellhammer archetype you are already using, so you will probably be good to go.

Another option are Rings of Wizardry with Alternative Source Spell feat from Dragon #325 - feat makes your casting arcane or divine, whatever you wish, and ring doubles your arcane spell slots at given spell level. Some 3rd party sources, like Gary Gygax's Necropolis, contain magic items that cost and works exactly like Rings of Wizardry, but under different names, on different body places (like amulet), and for divine casters. That way you don't even need a feat or anything. You can consult your DM about it - power-wise it shouldn't be a big issue.

Bonus Spells from ability score are natural way to increase spell slots, too. For every point of modifier increase, you (potentially) get slots for higher spell level, and for four points - more slots at the levels on which you already have bonus spell slots. So increasing Wisdom whenever you can should work. In addition to increase by level, you can use items and spells that boost your Wisdom. Headband of Inspired Wisdom, Periapt of Wisdom etc. Sadly, Owl's Wisdom explicitly excludes bonus spells from the list of it's benefits. Wish and Miracle do not.

Momento Magica (Magic Item Compendium, p. 164) allows you to regain a spell slot you have used. It actually works on slots, not spells, and does not have any limit on the way you spent your slot.

Last option is to get a lot of new spell slots from totally other class. You will loose a lot of Inquisitor's original fluff that way, so I wouldn't really bother, but here goes what I can think of:

1. Fochlucan Lyrist requires only one level in another base class, but a lot of tricks for other requirements. But it's casting is 10 + 10 / 10, so it has the lowest spell level / spell slots drop possible.

2. Mystic Theurge has easier requirements, but requires 3 levels in other base class - unless you use Alternative Source Spell feat to game the rules

3. Again with Alternative Source Spell, [Sublime Chord][10] PrC could give your character full casting progression. But too much requirement play - possible in theory, but hardly practical at all.

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Note that Mage's Lucubration and Pearls of Power are not useful for you. You are a spontaneous caster, and these items works for prepared spells. And even if you somehow find a way to prepare, they are not useful directly:

recall any one spell that she had prepared and then cast

 

prepare any one spell of 5th level or lower that you have used

As you can see, both requires you to actually use a spell, not a spell slot, so without some rule-bending wouldn't work on spell slots spent on Spelldrive. So they can help to save spell slots when casting spells, but that's all.

Answer 2

I think the best way to achieve this is via magic items, since doing so will leave the rest of your resources available for things you can't buy with gold. I also think you should dip a level of Cleric, which uses the same primary stat, so you can make use of the large advantage prepared casters have when it comes to spell slots. You only need one level as many spells on the Cleric list are also on the Inquisitor list and you don't actually need to be able to cast the spells you prepare as a Cleric, just able to keep them ready for Spelldriving. The spells you keep in this way don't technically even have to be on the Cleric list, but using only ones from that list is likely to keep your DM happier. You also don't technically need to be a prepared caster to use the Mage's Lubrication method, but dipping Cleric is likely to make people feel better about it, and also gives you a bunch of spell slots on its own (for the same reasons I advocate multiclassing below as a last resort). It's also suggested in the archetype's fluff.

(at-will) Mage's Lucubration

The most effective (if cheesy) way of doing this is probably to get an at-will wondrous item of Mage's Lucubration, if custom items are allowed. If not, some other unlimited source will suffice.

The method of use is as follows:

Cast any 5th level spell normally, as an Inquisitor (Commune is a good choice, since you should probably take the time to listen to your God every day anyways and it's on both the Cleric and Inquisitor lists).

Use Lucubration to regain the spell as a Cleric.

While (true)

Sacrifice the spell for Spelldrive.

Use Lucubration

Loop

You can't regain the spell you sacrifice to Spelldrive with Lucubration, but you don't need to because you can regain the same spell multiple times. You just regain your one casting of the spell with Lucubration as necessary. This is nice because it gives you infinite 5th level spelldrive.

Mnemonic Enhancer

This is basically a less good lower level version of Mage's Lucubration that takes 10 minutes to cast. Use it if your GM allows custom magic items and you can't afford Lucubration or they house-rule Lucubration to only be allowed to fill the same slot once or some such nonsense. It would let you replenish your spellslots between combat. If the 'three additional levels of spells' is allowed to stack, this can grant you 9th level cleric spells. As a result the spell levels almost certainly won't be allowed to stack, but you can still use it to be able to cast 2nd and 3rd level spells off your Cleric list that aren't on your Inquisitor list if you want to.

Obviously you should only use the 'Prepare' option; the 'Retain' option is useless.

Pearls of Power level I

You'll need a lot of them, but you can use them pretty much as above. Keep in mind that you lose a spell slot of a given level (by casting it) before you get any spelldrive benefits, so you need to have at least two pearls before you see any extra spell slots. This gives you access to lots of level I slots. You could also combine it with Mnemonic Enhancer to have lots of level II and/or III slots, but Mnemonic Enhancer is pretty good at that itself.

Other Options

If items aren't allowed, you can either take that Extra Spell Slots feat Molot was talking about or multiclass more. If you are playing a low-level campaign, I'd actually recommend multiclassing. Multiclass casters are stereotypically weak from a long-term optimization perspective, but very effective at low levels as they have tons more spell slots as anyone else and have a Will save that's twice your level can be really cool in the right situations. If you choose to multiclass I'd recommend Inquisitor/Cleric/Warpriest/Shaman so that you can maximise your spell slot bonuses from high Wisdom. With 20 Wisdom (human, point buy) this would give you 12/12 instead of 4/4/3 slots per day at level 4. Note that you will never cast even level 2 spells if you keep it up, which rapidly becomes a problem as spell quality outstrips spell quantity (around level 7 or so). You will also have very weird stats.

As a side note, increasing your casting stat (Wis) is the most important method of having more slots, especially at high levels. You should get every boost to Wis you can, especially if you are multiclassing as that multiplies the bonus directly. Unfortunately stat boosting items only go up to +6 unless custom items are allowed (and even if they are stats are very expensive) and wishes and such are only good for another +5. There are other methods of increasing your Wis by stacking various spell effects or exploiting strange spell interactions, but they are likely to get a book thrown at you.

Explanation Regarding Spells that Prepare Spells

The crux of this answer is that there are spells that let you have more spell slots, but they specify that those spell slots are prepared spells. If your ability to do this seems strange: The real trick is convincing the DM that in itself merely casting the spell--no matter the means--allows another spell to be "stored in [the Inq13/Clr1's] mind as though prepared in the normal fashion" even though the character A) can't store spells in his mind of that level, and B) can't prepare spells of that level in the normal fashion. That relies heavily on the DM agreeing that spells overrule class features, which is likely a very tough--but not impossible--sell. It is part of specific-overrides-general but it's still a very optimizing interpretation of the rules.