Back when D&D had prestige classes, Mystic Theurge was one of my favorites. This prestige class was made by multiclassing an arcane and a divine class. The class uniquely handled magic, however. Theurge’s sacrificed high-level spells in exchange for increased lower level spells. This change in spellcasting was mighty with the versatility you got from gaining more lower-level spells. That is why many players considered this prestige class the ultimate caster. This got me wondering, can we get the same effect in 5E? Obviously, multiclassing is very different in 3.5 compared to 5e. Still, I feel we can get a very similar result and can create the ultimate caster in 5e.
Multiclassing From Past To Future
When you multiclass in 3.5, very few things combined between classes. For example, if you took a level in the wizard and a level in bard, you treated all abilities and spells separately. This means that you had your bard spells and wizard spells, and you prepare them and cast them individually. This was great since you do not combine spell slots you get many lower-level spells to cast.
In 5e, however, multiclassing spellcasters combine their spell slots so you can never get more spell slots. This was done, so any multiclass will get the same number of spells per day as a full caster class. While this does not get you a plethora of lower-level spells to cast, it does give you access to higher-level spells. Also, just like with 3.5, you prepare spells separately, but we will get to that later.
What Makes Your Caster Ultimate
This is a good question when trying to make an ultimate caster. I believe versatility is a considerable part. Versatility makes sure that you always have an answer to a problem. The number of spell slots does not change whether you are multiclassing spellcasters together or not. Because of this having a spell for every scenario is extremely helpful. What even makes this better than the theruges of old is that you still have access to high-level slots making your spells powerful.
This build focuses on spells, not abilities from archetypes. You have free choice on any archetype you want. However, this build will recommend some archetypes that help fit with this theme.
The Ultimate Caster Trio
When creating the ultimate caster, you need to remember that not all classes are designed the same for multiclassing. In fact, three classes make up this build, Wizard, Druid, and Cleric. What makes these classes great for the ultimate casters is that all these classes let you prepare your spells from any level as long as you have the spell slot. You do not need to worry about having to level to get more known spells at higher levels. While druids and clerics get access to your whole list with wizards, however, need to have that spell in their book. This can be done by copying spell pages or scrolls into your spellbook.
Now that we have the three classes we are using, let go over what they each bring to the table.
The Magic Of The Woods
Druids are the low class on the totem pole compared to the other two. None of their archetypes really have anything that helps with the ultimate caster build. However, this is fine since all you need is one level in druid to gain access to all their spells, which they have some of the best, in my opinion. This is because, as mentioned, above to prepare a druid spell of a certain level, all you need is a spell slot of that level.
The Divine Power
Clerics are a staple in this build, and the one I recommend leveling up the most early on. Clerics prepare spells just like druids and even rely on the same ability scores. The domains are where they get their strength. They give you extra spells that are always prepared and can also contain spells clerics cannot usually get. In this build, the domain you pick is up to the bonus spells you want.
The Spellbook That Brings Power
Wizards are the other powerhouse class in this build. While you don’t get immediate access to your spells at higher levels like druids and clerics, you can add those spells to your book to still gain access to them. Also, Arcane Recovery can give you a few spells back when you short rest. One of the best things this class has to offer is that their ritual spells just need to be in the book and do not need to be prepared. The schools don’t matter much in this build and are up to player choice.
Bringing All Three Together
As stated above, this build is more focused on spell casting but will mention some archetypes that may help with your spells’ utility belt. You also only need two ability scores, intelligence, and wisdom, since druids and clerics both use wisdom. When starting this build, you take one level in every class before you continue leveling up in those classes. That way, you get access to all the spell lists early on. When choosing the classes in which order, the second and third levels do not matter, but the first should be a druid. Druids give you excellent starting health. The saves align with both the ability scores you are using and the skills they have access to have a superb selection between wizards and clerics.
I would go a 10-9-1 level split with 10 levels in wizard, 9 levels in cleric, and 1 level in druid. You could switch wizard and cleric if the level 10 arcane tradition is worse then divine intervention. The reason you get an almost perfect split between wizards and clerics is because of their abilities. Arcane recovery is excellent with the higher wizard levels giving you more spell slots back. Clerics get bonus spells prepared at the more they level, which increases your versatility.
Spells, Spells Everywhere
You may be wondering how many spells do you actually prepare with this build? Let’s find out assuming a level ten character with 1 level in druid, 5 levels in cleric, and 4 levels in wizard. We will also presume a 16 in both intelligence and wisdom.
Druid (2) Cleric (4) Wizard (4) Total: 10
Druid (4) Cleric (14) Wizard (7) Total: 25
If you are wondering about the cleric’s spike, it is from all the spells they get prepared from their domains.
This is quite a lot of spells you can prepare and does not count the wizard’s ability to ritual cast spells that are not prepared. When considering what spells to prepare, try going for a mix of everything. Have every type of attack damage you can grab to always attack enemies’ weaknesses. Have spells to keep allies alive and to let you escape from imprisonment. With all these spells ready to cast at a moment’s notice, you will have multiple options to handle any situation.
The Archetypes That Count
Even though you are free to choose the archetype you want. Certain ones can help out with your spell casting. I will be using only official archetypes, But there are some UA that are just as good.
The channel divinity gives you max damage on all lightning spells including the ones you get from your druid and wizard spells
This awards you bonus health shield when casting any abjuration spell regardless of the spell list
You can add your proficiency to counterspell and dispel magic
Can let ally avoid damage from AOE spells
Cantrips that when saved against they take no damage now take half which is excellent for cleric cantrips
Bonus to defense but can’t cast a non-cantrip spell the turn after which can be easily negated by the Druids call lightning or the cleric’s spiritual weapon spell
Feats Of Magic
There are two feats you may consider taking to increase your spell versatility, magic initiate, and ritual caster. Magic initiate gives you two cantrips and a 1st level spell form the bard, cleric, druid, sorcerer, warlock or wizard spell list. This can bolster cantrips from the classes in this build or add some unique power from another class. Ritual caster acts the same way wizards cast ritual spells and can be a great way to add spells from other spell lists.
Races That Excel As Ultimate Casters
When Looking at what species to play, go for classes that give bonuses to intelligence and or wisdom. You can also choose one that offers a cantrip, for example, Aasimars. I also like humans since you can select one of the feats mentioned above at first level.
Things To Note
While it may not seem like the druid level is essential, they have impressive offensive spells like call lighting and powerful utility spells like transfer via plants. It is worth taking a single level.
In the sage advice, compendium cantrips are stated as leveling up with character level, making all you cantrips grow regardless of class level.
Since you do not gain ability score increases as often, try separating your offensive and defensive spells by druid/cleric and wizard. Basically, making one ability score the focus of saves and attack rolls while making the other ability score cast spells that require neither.
As stated many times above (my players tend to forget, so I wanted to enunciate). Wizard ritual spells do not need to be prepared to add as many as you can to your spellbook.
The Wrap Up
And that is how to make the ultimate caster build. Remember that it focuses on spell casting and not class abilities, which may feel a little weird. Feel free to take the archetypes I recommend or one that fits your character’s story. Either way, your spell casting prowess will make your enemies tremble.