Trying to determine if there are items aside from using the ring of spell storing, or items that simply directly increase intelligence score, that can increase a wizard's number of spell slots per day?
There are, but not much.
These are the two items I could remember:
- Pearls of Power (DMG): These items let you reprepare a spent slot with the magic previously spent. It doesn't add more slots, but adds versatility so you can prepare less repeated spells and use the same spells slots more than once. Best of all, doesn't occupy a magic item slot.
- Ring of Wizardry (DMG): The dream of every wizard apprentice that unfortunately only some masters end up grabbing one. Each of those rings are associated to a spell level, at that level, your base slots are doubled, not extra slots from high intelligence or school specialization, just the ones from the Wizard table.
Other items may improve your spell management during the day without increasing your slots directly:
- Wands: If you use a spell frequently and if caster level or save are not important for that spell (ex: Snake Swiftness, Celerity etc), using a wand extend greatly your spell management and add versatility for you as it opens slots that you would prepare with them.
- Staves: Same as wands but better since they use your caster level if higher and your spell save DC. If not enough, staves can have multiple similarly thematic spells on them.
All other slot increase methods I could remember came from feats (ex: Extra Slot), class choices (ex: School Specialization), prestige classes (ex: Ultimate Magus) or atribute increase (ex: Headband of Intellect).
PEARLS OF POWER !!!
Those beauties come in all levels, and allows you to multiply what you may have... they have uses for the whole party, not just the wizard... Especially after a major fight, when you can re-stock.
They do not ADD to your number of spell slots, but they allow you to use more of what you prepared, which usually is just as good.
Besides increasing that necromancer's Intelligence score, there aren't many magic items that grant additional spell slots. The big one is…
A ring of wizardry (Dungeon Master's Guide 223) (20,000+ gp; 0 lbs.) doubles the number of arcane spells the wearer can cast per day (excluding bonus spells from, like, a high Intelligence or school specialization) of one spell level from 1st- through 4th-level, with pricier rings doubling higher-level spell slots. A ring of epic wizardry (Epic Level Handbook 136) (250,000 gp; 0 lbs.) similarly doubles spells of one spell level from 5th- through 9th-level.
This DM would not allow multiple rings that double the same spell level to combine for a cumulative effect—tripling or quadrupling spells of that level—, but he would allow a particularly wealthy arcanist to combine multiple rings of wizardry into a lone ring at the Magic Item Compendium price of an additional +50% for each less expensive item plugged into the most. (For example, a ring of wizardry I, II, and IV would have a price of 190,000 gp and double the wearer's 1st-, 2nd-, and 4th-level arcane spells per day.) Y'know, if that necromancer's ring slots were at a premium or something.
There are alternatives to the ring of wizardry, but they're… difficult.
- Go on a quest for the rod of Valmaxian (Magic of Faerûn 171) (minor artifact; 4 lbs.) "gives a spellcaster an additional spell slot at each spell level she can cast," but these slots (and the spells prepared in them) vanish if the creature stops touching the rod.
- Go on a quest for the helm of supreme wizardry (Dragons of Faerûn 131) (minor artifact; 3 lbs.), among other effects, "allows any wearer already able to cast wizard spells to prepare and cast two additional spells of each level from 6th through 9th (8 spells per day total)." The helm deals damage to the wearer when he casts these extra spells.
Convince the DM that a memento magica (Races of the Dragon 124) (1,500+ gp; 0 lbs.) works for prepared casters. That is, the description begins by saying, "A memento magica is a great aid to spontaneous spellcasters such as sorcerers, bards, and favored souls…, much as a pearl of power is to casters who prepare spells." Then the description says what it actually does for the bearer:
Once per day on command, a memento magica enables its possessor to regain any one spell slot that she had previously used that day. The spell slot is available just as if a spell had not been cast.
The Player's Handbook on Spell Selection and Preparation says
When preparing spells for the day, a wizard can leave some… spell slots open. Later during that day, she can repeat the preparation process as often as she likes, time and circumstances permitting. During these extra sessions of preparation, the wizard can fill these unused spell slots. (178)
For example, a wizard takes a standard action to cast at the darkness the 1st-level spell magic missile. Realizing her error, next turn she takes a standard action to activate her memento magica (1st) to regain her 1st-level spell slot that previously contained the spell magic missile but is now open. She can take 15 min. to prepare a new spell (perhaps even magic missile again) in that open slot.
Now, a DM could reasonably rule that since the spell slot regained by the memento was not left open at the beginning of day the wizard can't prepare spells in that slot… despite the slot's existence and despite the slot being open. Seriously, this player would not, like, flip the table and storm off because of such a ruling. However, this more permissive DM thinks because the memento price is 50% more than a pearl of power of the same level that the memento's allowed to offer a prepared caster some increased versatility in exchange for speed.
Convince the DM that a strict reading of the pearl of power (DMG 263) (1,000+ gp; 0 lbs.) allows the bearer to regain the ability to cast any spell of that pearl's indicated level that the prepared caster has ever prepared then cast. This reader does not support this line of inquiry and includes it for completeness! The description of the pearl of power says, in part, that
Once per day on command, a pearl of power enables the possessor to recall any one spell that she had prepared and then cast. The spell is then prepared again, just as if it had not been cast. The spell must be of a particular level, depending on the pearl. Different pearls exist for recalling one spell per day of each level from 1st through 9th and for the recall of two spells per day (each of a different level, 6th or lower).
Unlike the memento that specifies a "spell slot that [the bearer] had previously used that day," the pearl cares only that the spell had once been prepared then cast ever. Did the level 7 necromancer last cast ray of enfeeblement when he was level 3 but needs it right now? That pearl of power (2nd) can get it!
This is, of course, abusive. This DM and player recommends using the pearls of power the way it seems they're supposed to be used: to regain expended spells that were prepared the last time a creature prepared spells. Honestly, pearls of power are already good enough. Either way, a pearl of power doesn't really get the necromancer more slots but, instead, recycles used slots. However, that makes it no less versatile.
The belt of the dread emperor (Book of Vile Darkness 114) (120,000 gp; 1 lb.) lets the wearer chain a humanoid (specifically!) to the belt then the belt "enables the wearer to recall a prepared spell, even if the spell has already been cast, as long as the spell was among those he most recently prepared" but the creature chained to the belt is dealt damage equal to the spell level of the recalled spell squared. If that damage would kill the creature, the creature dies and the spell isn't recalled. Like the pearl of power, the belt doesn't get the necromancer more slots, but it's close.
Really, this reader recommends sticking with pearls of power (used conventionally!) and rings of wizardry supplemented by—with DM approval—some mementos magica until the necromancer can discern the resting place of the the rod of Valmaxian. That is, unless the belt of the dread emperor sounds attractive—maybe that necromancer already has kender in mind…?
The Spell Storing weapon enchantment "... allows a spellcaster to store a single targeted spell of up to 3rd level in the weapon. (The spell must have a casting time of 1 standard action." Then, when the wielder of the weapon hits and damages a creature with the weapon, they can choose to cast the spell on that creature. Once the spells been discharged, a new one can be stored.
Rod of Absorption absorbs single-target spells targeting the possessor of the rod or his gear. The possessor can then later used absorbed spell levels to cast spells they have prepared without losing the prepared spell. They just expend a number of absorbed spell levels equal to the level of the spell they wish to cast. They must be holding the rod and the spell still uses its normal material components. The rod is capable of absorbing and then subsequently utilizing 50 levels of spells.
One could enchant a headband capable of Rary's Mnemonic Enhancer a certain number of times per day for 11,200gp per daily charge. Each charge would allow the user to either memorize three additional levels of spells or regain in memory a spell of third level or lower cast the previous round. A specific DM might rule that a given magic item was only capable of doing one or the other, not both functions, and the DM would also have to decide if multiple charges would be able to allow a caster to memorize extra spells of higher than 3rd level, as the spell description doesn't specify whether multiple castings of the spell can stack.
protected by doppelgreener♦ Feb 16 '18 at 9:44
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