Arcane Polymath

The newcomer studied the Dark Magic with the ancient warlock. But when it came time to invest him with the power of their dark liege, the neophyte was gone. The ancient master shrugs, knowing that her patron's secrets are safe and unusable without investiture. At least, that is what she had been taught.  

The precocious apprentice was warned that their spell design incorporated extraneous foundations and did not utilize the necessary gesture that the spell school used to connect to magical power. When it worked anyway their master begrudgingly gave them a passing mark, although they themselves could never replicate the spell design. 

The exchange student couldn't even play the lyre and was most certainly tone-deaf. However, the cadence of the spell felt true, and the bard watched in wonder as the strange wizard healed the wounded.

When a Wizard learns to cast spells, their instruction is usually tied to eight magical Schools. Each of these schools uses a particular type of energy and requires certain fundamental elements to cast, be they particular intonates or specific gestures or some other metaphysical framework. In other words, the components of spells from the same school tend to be similar. Schools demonstrate that the different spells of a school are related not only in their effects but also by how they are produced. However, there are some arcane spells that do not operate this way, with components that break the Wizard's school metaphysics. The most well-known is Cure Wounds, which practically every Wizard has seen at some point in their career. Most Wizards cannot cast these spells.

Most Wizards, but not all.

Unwilling to focus on any specific school of magic or particular practice, Arcane Polymaths prize knowledge and flexibility above all other things. These Wizards study the spells of other arcane classes and integrate them into their repertoire. Their guiding theory is that any barriers between the capabilities of spellcasters without a divine sponsor are only enforced by tradition, practice, and a lack of imagination and understanding. As such, they master spells thought impossible for Wizards to cast. Some Arcane Polymaths hope to share their fascinating discoveries with the world and change how all Wizards are trained, while others seek knowledge for their own satisfaction and power, collecting arcane secrets like a dragon hoards treasures. A rare few believe overcoming this limitation of mortal magic is key to divine ascension for a Wizard. 

Notes: This Wizard subclass automatically adds spells from the Wizard Spells addendum in the Unearthed Arcana Class Feature Variant to the Arcane Polymath spell list.

Version 5 of the subclass removes the duplication of spells from the spell lists. I just added them individually up-front instead of adding the four entire lists (should have thought of it that way in the first place). This approach does mean that licensed spells cannot be added to the character sheet, so if you want one of those you need to use version 4 (and to own the licensed spell in question). Those spells (and the sourcebook that contains them) are: Magic Stone (EEPC), Thorn Whip (PHB), Armor of Agathys (PHB_, Arms of Hadar (PHB), Chaos Bolt (XGtE), Dissonant Whispers (PHB), Hex (PHB), Hunger of Hadar (PHB), Motivational Speech (AI), Power Word Heal, (PHB) and Shadow of Moil (XGtE). 

Since I added all the spells up-front, I reordered the class features to rebalance the subclass. I also added detail on copying spells and made Arcane Polymath spellbooks harder to decipher than those of other Wizards.

5.1: Fixed a few typos and level discrepancies. 5.2 Removed Ice Storm from additional specific spells. 5.3 Fixed Wizardly Anamnesis short description to match class full description. Added back Fire Storm. 

Recondite Spellcasting

At 2nd-level you gain access to the spell lists of the other arcane spelling classes (Artificer, Bard, Sorcerer, and Warlock). This access gives you the ability to learn some spells that are excluded from the Wizard spell list. The essential ingredient or element in these spells that prevent Wizards from using them is not a settled debate amongst Arcane Polymaths. Some speak of specialized metaphysical frameworks outside of those used in the Schools, invocations that tap into ancient, dormant powers, using parts of the fabled Words of Creation, and even the suspension of personal belief as key. Most other Wizards scoff at these hypotheses, but they cannot deny that their application has stretched the boundaries of Wizardry for the Arcane Polymath.

You continue to choose spells from your spellbook to prepare as normal, your spellbook will just have some unusual spells in it. These spells count as Wizard spells for you. You choose from your entire spell list including these spells when you add spells to your spellbook for gaining a level. You can copy more of these spells into your spellbook from scrolls you find, using the rules for Copying a Spell into the Book described in the Polymath Spellbook feature of this class.

These spells specifically added to your spell list are: 

• Cantrips: Eldritch Blast, Guidance, Resistance, Spare the Dying, Vicious Mockery
• 1st Level: Animal Friendship, Bane, Cure Wounds, Faerie Fire, Healing Word, Hellish Rebuke, Heroism, Purify Food and Drink, Sanctuary, Speak with Animals
• 2nd level: Aid, Animal Messenger, Calm Emotions, Enthrall, Heat Metal, Lesser Restoration, Locate Animals or Plants, Protection from Poison, Silence, Zone of Truth
• 3rd level: Create Food and Water, Daylight, Plant Growth, Revivify, Speak with Dead, Speak with Plants, Water Walk
• 4th level: Compulsion, Dominate Beast, Freedom of Movement
• 5th level: Awaken, Greater Restoration, Insect Plague Mass Cure Wounds, Raise Dead
• 6th level: Conjure Fey, Find the Path
• 7th level: Fire Storm, Regenerate, Resurrection
• 8th level: Earthquake, Glibness

Perplexing Spellbook

Arcane Polymaths pursue an individualistic style of spellcasting, significantly different from their fellow Wizards. They combine elements from different school theories in unorthodox and sometimes contradictory ways that baffle other Wizards. As such, their spellbooks are harder for others to decipher.

A Wizard attempting to copy a spell on their class list from an Arcane Polymath's spellbook into their own must succeed at an Intelligence (Arcana) check with a DC of 15 + Spell Level to successfully understand a spell and construct a working version of it into their spellbook. Another Arcane Polymath gets a +5 bonus on this check. A Wizard who fails to decipher a spell cannot try again until they gain a Wizard level. A Wizard cannot copy a spell not on their spell list into their spellbook. 

Arcane Polymaths use the following rules for copying spells into their spellbooks instead of the ones listed in the Wizard class features.

Copying a Spell into the Book. When you find a spell of 1st level or higher that is on your expanded class list, you can add it to your spellbook if it is a spell level you can prepare and if you can spare the time to decipher and copy it. Copying that spell into your spellbook involves reproducing the basic form of the spell, deciphering their unique system of notation sufficiently to determine the necessary framework elements, and extrapolating from their work to create a functioning version of the spell.

Because you do not always need to fully decipher another spellcaster's notation system for the entire spell, you can sometimes copy spells from other spellbooks faster than other Wizards. However, your process is more experimental and can fail, requiring you to fully decipher the spell notation. You must succeed at an Intelligence (Arcana) check with a DC of 10 + Spell Level to create a working version of the spell. If you succeed, you combine component requirements together in a unique way that produces a working version of the spell. For each level of the spell, the process takes 1 hour and costs 50 gp.  If you fail, you can still copy the spell, but you must fully decipher the spell notation. The process takes 3 hours per level of the spell instead of 1, but still costs 50 gp per level of the spell. Once you have spent this time and money, you can prepare the spell just like your other spells.  

Improved Prestidigitation

At 6th level, you learn the Improved Prestidigitation cantrip. The cantrip doesn’t count against your number of cantrips known.

Wizardly Anamnesis

At  6th level, your eclectic spellcasting style and practice with fundamental frameworks have given you the ability to quickly change your list of prepared spells without the eight hours of rest and study normally required.

Once per day following a short rest, you can prepare a number of spells up to your proficiency modifier. At this time, you can also choose to abandon (un-prepare) a number of spells with a total sum of spell levels less than or equal to half your Wizard level, plus your Intelligence (INT) modifier to make room for these spells. The spells you abandon can be any level, but their total spell level must still meet this requirement. 

You must spend at least 1 minute per spell level for each spell you add to your prepared spell list. This time is spent memorizing the incantations and gestures you must make to cast the spell. Prepared spells must be in your spellbook, which you still must use to prepare spells. You cannot prepare spells above 5th level in this way.  Abandoned spells must be from your Wizard list of spells prepared. It takes no additional time to abandon spells. 

You are still limited to a number of prepared spells equal to INT mod + Wizard level, and spells you prepare must be of a level for which you have spell slots (even if expended). You can use both Wizardly Anamnesis and Arcane Recovery after the same short rest.

Note: When you prepare spells, you can leave some spell slots unprepared for the purpose of preparing them later. Normally this practice is a bad idea, but you might have a reason to quickly prepare more spells than you can abandon. You can abandon spells above 5th level with this subclass feature, as long as the sum of the levels of the abandoned spells is less than your Wizard level divided by two, plus your INT modifier, i.e., (Wizard Lvl / 2) + INT Mod. 

Cantrip Mastery

At 10th level, your study into alternative spellcasting methods has given you a deeper understanding of the simplest spells. 

You can attempt to cast a cantrip that you do not currently know. The cantrip must be on the Wizard, Artificer, Bard, Sorcerer, or Warlock spell list, and you must succeed on a DC 10 Intelligence (Arcana) check. If the check succeeds, you cast the spell. If the check fails, so does the spell and your action is wasted. You can attempt to cast a cantrip you do not know a number of times per short rest equal to your proficiency bonus.

Also, when a creature succeeds on a saving throw against one of the cantrips you know, the creature still takes half the cantrip’s damage (if any) but suffers no additional effect from the cantrip.

Unmatched Arcane Versatility

At 14th level, your arcane enlightenment lets you skirt some of the rules of Wizard spell preparation on the fly.

As a bonus action once per day, you can abandon one spell you prepared and make a different spell from your spellbook available in its place. The spell you make available must be 5th level or lower, although the spell you abandon can be of any level. You must have one of your spellbooks that contains the spell open to the place where the spell is recorded. You can cast the spell normally as though it was prepared until the next short rest, as long as you refer to your spellbook when you do.

The spell is not fully prepared--instead, you use your spellbook to fill in the gaps in your memory until you have time to finish preparing it. You can fully prepare the spell by studying it for one minute per spell level before or during your next short rest. When you finish a short rest, the available spell must either be fully prepared or it is abandoned. You do not recover the original abandoned spell when this happens. 

You regain this ability whenever you complete a short or long rest.