Paladin 2 / Wizard (abjurer) X
You said you are willing to take at most a 2 level dip in another class for proficiencies. Have you considered taking these levels in Paladin? Assuming you want to keep the "I'm a Wizard!" flavour, taking your first 2 levels as a Paladin of the god of magic (assuming there is one in your campaign, of course) isn't really out of character. So here's my take on this build. I'll mostly cover melee options, since this is what the question is about, but you should still be able to do anything that another wizard could do, just 2 levels later. This gap can be great at certain levels (Fireball is a great damage upgrade at level 5), but it shouldn't be noticed too much on single target damage (Smite!). It's not the strongest build out there, but it's definitely good enough to be enjoyable!
Benefits of 2 paladin levels :
- Proficiency with all weapons : opens up many solid weapon choices
- Proficiency with all armors and shields : although dex is definitely the best stat in 5E, a melee wizard will require spending spell slots on defence to keep up. Being able to wear a full plate and a shield gives great defensive benefits and costs no daily ressources.
- 6 more HPs : While 2 more level wizard levels would've given you 4 more arcane ward HPs, those only replenish on a long rest or by spending spell slots. Arcane ward is an awesome feature, but real HPs trump it anytime.
- Lay on Hands : Yay for 10 free HPs per day! More than makes up for those 4 lost ward HPs, and can be used on other people, too.
- Fighting style : There are many good options here, but I'd go for protection or defence to increase your utility/survival. Great weapon fighting is a good offensive option if you forgo your shield and grab a great sword, especially since you're going to stack lots of dice on those attacks. This can be somewhat replaced by the Elemental Adept feat, however.
- Access to 1st level paladin spells : One thing you'll have as a wizard is lots of low-level spell slots rather early. Smite spells might not always be the best options, but they can add good damage and other effects on your melee attacks. Paladin also has a few abjuration spells, which gives you back some arcane ward HPs, but the good ones are higher level, sadly. If you have the warcaster feat and can handle your constitution saves, Shield of Faith is also very good as a low-cost defensive boost. While Cure Wounds is a paladin spell, you can cast it using your full spell slots, which means that, although not a cleric, you still have access to some great healing powers if they are needed.
- Divine Smite : Convert spell slots into damage. Given that you can elect to smite after you know the attack hits, and that there is no save for this damage, it's a great way to increase your melee damage. Especially good if you crit...
That being said, given equal gear, you should have the same AC as any other tank, since you're wearing the same stuff they are. As for your damage, the new Sword Coast Adventure Guide cantrips are there for you. Sure, they're not going to out-damage a fighter or a rogue, but they're still very good damage options. Since they require a melee weapon attack, they also trigger class features such as Divine Smite, so you don't miss out too much. Having two attacks could technically mean 2 smites per round, but the added damage of your cantrips will compensate for this quite decently.
- Green-Flame Blade : when fighting multiple enemies, this attack basically gives you the benefit of a second attack without costing anything. Since you're not going to have multiple attacks from class features, this is pretty much as good as you're going to get.
- Booming Blade : Assuming you can make sure your opponent moves willingly each round, this cantrip will give you the same benefits as GFB except on a single target.
Other thing to note is that the secondary damage from these spells automatically hits, no save and no attack roll required, which means that you can strike a minion to land free damage on the BBEG. These spells will thus give you decent damage round after round, leaving you with all your other spell slots to use as you see fit. Your 2 levels of paladin will give you the opportunity to convert your low-level spell slots into more damage as an option, and your wizard powers will allow you to turn these same spell slots into defensive abilities. Shield will grant you +5 AC for one round, which is awesome if you attract the BBEG's attention (especially given that your AC is already high). In Elemental Evil, there is also the Absorb Element spell, which gives you resistance against a single element, also for one round. This gives you defensive options for both physical and most magical attacks. As an interesting addition, both of these spells are abjuration-based, and will thus heal your ward for 2 HPs every time you cast them.
And after all this, you're still an almost full wizard. Your access to spells and features will be delayed for two levels because of multi-classing, which shouldn't reduce your melee effectiveness, but you will still have access to 9th level spells and have spell slots as a 19th level caster. While the Signature Spell capstone is good, the real treat is at wizard level 18 (character level 20 for you), so you don't miss out on much. Indeed, spell mastery will allow you to have 2 low-level at-will spells, which gives you infinite Shield spells, for instance. This should allow you to use your slots for more offensive options, since your defence is free. Infinite Shield spells also means that your arcane ward is always topped off after every combat if you take a minute or so to recharge it after each fight.
Your melee power also scale quite decently if we compare them to a tank fighter (longsword + shield, defensive fighting style) of equivalent level :
- Level 1-4 : Fighter [1d8 + str] vs GFB [1d8 + str + (int secondary)]
- Level 5-10 : Fighter 2x[1d8 + str] vs GFB [1d8 + 1d8 + str + (1d8 + int secondary)]
- Level 11-16 : Fighter 3x[1d8 + str] vs GFB [1d8 + 2d8 + str + (2d8 + int secondary)]
- Level 17-19 : Fighter 3x[1d8 + str] vs GFB [1d8 + 3d8 + str + (3d8 + int secondary)]
- Level 20 : Fighter 4x[1d8 + str] vs GFB [1d8 + 3d8 + str + (3d8 + int secondary)]
Of course, a fighter has abilities to increase his damage, but so do you (thank you, Divine Smite)! Since the fighter has more attacks, he's more likely to deal some damage each round, whereas your damage all hinges on your single attack landing. This will be especially important if the fighter can get his hands on a weapon that deals extra damage (like a flame tongue), an ability that would be mostly wasted on your single attack per round. The fighter also only requires only one good stat to be 100% effective, while you will need both strength and intelligence. Since your intention is to go melee, I'd consider maxing strength first, especially considered you'll use your spells mostly defensively or in a utilitarian fashion (so lower save DCs are not as bad).
Feats to consider :
- Warcaster : For pretty obvious reasons (casting and adv. on constitution saves). Combined with Booming blade, it's also a boost to damage: when an enemy tries to get away, you booming blade it, which will deal almost double damage if it hits, as the enemy will likely leave the area right after. If they don't, well, your party gets to kill them anyways.
- Shield Master : If you are using a shield, it's a solid defensive feat.
- Heavy Armor Master : +1 strength, reduce most physical oncoming damage by 3. The drawback is that it doesn't work on your arcane ward, as it has it's own HP pool. As such, any damage the ward takes is not "damage that you take" and does not trigger this feat. Still a great option for a tank, especially one that has a wizard's HP pool and requires strength for his attacks.
- Elemental Adept : You're going to cast a lot of fire cantrips, and this feat allows you to ignore resistance and to treat 1s as 2s. This feat does not specify that only the fire damage dice are affected, so it works on your weapon die, your GFB dice, but also on your added Divine Smite dice. Definitely not bad.
- Mage Slayer : Disrupt enemy spellcasters from melee range. The attack granted by this feat is not as strong as a full opportunity attack (as warcaster will allow for a GFB or BB cantrip), but if you can prevent them from casting, it has a lot more utility. Advantage on saves isn't exactly bad either.
Other things to consider :
- Transmuter instead of abjurer : possible proficiency with constitution saves or resistance to one element is a good trade-off for a melee wizard. Not sure that I'd sacrifice arcane ward for it, though. Since Arcane Ward has it's own HP pool, all the damage it soaks isn't counted towards the concentration save DC. Advantage from warcaster should be more than enough, especially if you have some stat bonuses.
- Bladesinger instead of abjurer : A tough one... Since you're going to use cantrips for offense, you're wasting the extra attack feature with that build. But... a dex-based character wearing light armor will have only 1 less AC than a plate wearing character (equal if you cast mage armor instead), so your bladesong will leave you with a net +2 to AC during a fight once you get 20 intelligence (since you're also forgoing your shield). Even if not going for a strength build, you lose none of the advantages of a paladin (smite, armor proficiencies, healing, spells, etc.), but also gain Intelligence bonus to concentration saves and increased combat speed, as well as overall better skills since dexterity is the best stat. I'd personally favour bladesinger, but both options are very interesting.
Caster Level Looping
I'm going to open this answer by saying - there is no definitive rules text on how to treat, or in what order, stacking caster levels from classes or prestige classes. There is a general rule from the 3.5e FAQ that states that 'in general' one should apply bonuses in order most beneficial to the creature, but it's not exactly specific, or definitive, especially in this edge case.
Also, Caster Level Looping And You (by Bauglir) has how the CO people think all this works, also, nearly every way to multiplicatively increase Caster Level in the game.
It's worth noting that there are two ways to read this. One (the one CO likes) is that 'spellcaster level' is referring to 'caster level', and indeed, this is actually the way the game parses it in other abilities. But it could also be referring to 'levels in spellcasting classes', which means basically NONE of the shenanigans outlined here will do anything.
In my answer, I will be assuming the former, due to the way the question is asked. In the case of the latter, simply count up your class levels in arcane casting classes (which doesn't include PrC's that say '+1 level in existing blah', tough luck), and that's your CL for everything.
It's worth noting that former reading is not suitable for play or practical optimization in any sense. Neither are any of the other caster level loops, even (or especially) the ones that are written more explicitly.
But on to the questions.
Question 1
Alex is a Spellthief 2 / Wizard 16 / Green Star Adept 2 who possesses the feat Master Spellthief. What's Alex's caster level for his wizard spells?
Alex's Master Spellthief feat means his Spellthief CL is 18 (16 Wizard + 2 Spellthief) and his Wizard CL is 18 (''), before he takes any levels of Green Star Adept, 'when determining caster level for arcane spells'. So for arcane spells it's 18, otherwise it's the normal numbers - 2 for spellthief, 16 for wizard. This is fine, as the numeric effects of Arcane Spells is kind of what you want to use a caster level for as an arcane caster. But it's important to note that his caster level is still just 2, and 16, not 18.
So when he takes Green Star Adept, he adds his Green Star Adept levels (2) to his Wizard levels (16) to get his new Wizard 'effective caster level' (18). So he now has three things related to being a Wizard;
His Actual Wizard Caster Level: 16
His 'Effective' Wizard Caster Level: 18
His Wizard Caster Level For the Purposes of Casting Arcane Spells: 20.
There's no reason why 'effective caster level' would not be counted as a caster level for the purposes of Master Spellthief, so 2 + 18 = 20 = what you use as your CL for arcane spells cast either from the Spellthief class or the Wizard class.
Additionally, the Wizard has the spells known and per day of a 17th level Wizard, due to Green Star Adept's Spells per Day/Spells Known class feature.
Question 2
Bob is a Spellthief 4 / Wizard 15 / Knight of the Weave 1 who possesses the feat Master Spellthief. What's Bob's caster level for his A) spellthief spells, B) wizard spells, and C) knight of the weave spells?
And here starteth le fromage. Basically, Knight of the Weave's caster level is equal to Bob's Spellthief AND Wizard caster levels added together, but again NOT the Master Spellthief total, which is purely for the purposes of casting arcane spells only. So 4 + 15 = Knight of the Weave Caster Level of 19.
But whenever Bob casts an arcane spell, Master Spellthief kicks in. And it goes 'hmm what caster levels you got', finds Spellthief at 4, Wizard at 15, and some wacky prestige class called Knight of the Weave at 19, and then adds all those numbers together because they are all 'arcane spellcaster levels' and comes out with the absurd number of caster level of 38 for the purposes of casting arcane spells.
Question 3
Chris is a Bard 1 / Spellthief 1 / Wizard 8 / Sublime Chord 10 who possesses the feat Master Spellthief. She applies the sublime chord class feature spells per day to her wizard casting. What's Chris's caster level for A) wizard spells and B) sublime chord spells?
Sublime Chord sets all arcane casting classes Caster Level to 18, in this scenario, due to the wording of it's 'spells per day' ability.
Then along comes our good friend Master Spellthief, sees 4 Caster Levels (Bard, Spellthief, Wizard, Sublime Chord) set at 18. It goes, you know what? Let's add all those together, and end up with a CL for the purposes of casting Arcane Spells of 72.
Then everyone cries.
Question 4
Dylan is a Sorcerer 1 / Spellthief 4 / Wizard 3 / Ultimate Magus 10 who possesses the feat Master Spellthief. He applies the ultimate magus class feature spellcasting and extraordinary ability arcane spell power to his wizard casting when he can and his sorcerer casting when he must. What's Dylan's caster level for his A) wizard spells and B) sorcerer spells?
He starts out with Sorc CL 10, Spellthief CL 4, Wizard CL 11. He possesses a +4 to CL for the purposes of arcane spells. Master Spellthief turns his CL for all his arcane casting classes for the purposes of casting arcane spells into 25 (4+11+10). To which you then add +4. Master Spellthief (under the nice reading) sums the totals of your caster levels, not the totals of your 'caster level for the purposes of arcane spells', so UM's ability simply adds, it doesn't get multiplied across.
Question 5
Ethan is a Bard 1 / Sorcerer 1 / Spellthief 2/ Wizard 3 / Green Star Adept 2 / Knight of the Weave 1 / Sublime Chord 6 / Ultimate Magus 4 (or another more favorable combination you choose) with the feat Master Spellthief. He applies everything he can to his wizard casting until he can apply it to his sublime chord casting and everything he must to his wizard casting or his sorcerer casting, favoring wizard. What are his caster levels for his A) bard spells, B) sorcerer spells, C) wizard spells, D) knight of the weave spells, and E) sublime chord spells?
Why are you doing this to me.
Right. Following the FAQ guideline about adding things in most beneficial order, this is actually relatively simple. Ultimate Magus advances Sublime Chord 2 steps (you'd be better off just taking more wizard levels, you only care about highest non-sublime-chord CL when sublime chord is in the mix, and dipping as many other arcane casting classes as possible), putting total 'sublime chord levels' at 8. Sublime Chord adds itself to Wizard to determine your CL for ALL arcane spellcasting clsases, so all your arcane spellcasting classes now have a CL of 3+8=11. Green Star Adept adds +2 to Sublime Chord on top, so you end up with a CL of 13 on all your arcane casting classes.
Knight of the Weave now does it's thing. You can't have it do it's thing 'first' and then add sublime chord to it and then have everything be CL 22 or something because Sublime Chord adds itself to 'level in a spellcasting class', not 'CL'. So '+1 existing level' prestige classes etc mean nothing to Sublime Chord unless they are advancing Sublime Chord, since it determines it's CL based on class levels in another class + Sublime Chord levels/prestige class bonuses/stuff. Anyway, you've got 5 caster levels (Bard, Sorcerer, Wizard, Spellthief, Sublime Chord) and Sublime has set them all to 13. So, 5x13=65, +1 for your Knight of the Weave level, gives a Knight of the Weave CL of 66.
Master Spellthief then does it's thing when you go to cast a spell, as normal. 66+65= CL 131.
Then Ultimate Magus does it's Arcane Power thing for +2 more, giving you a final total of
CL 133.
Important Concepts for Understanding This Stuff
Prestige classes that advance spellcasting do not themselves have a 'caster level' - they simply modify the caster level and spells known etc of another class.
'Caster level' is not the same as 'caster level for the purposes of arcane spells', it's like 'hp while raging' or 'hp while buffed with Aid' is not the same as 'base hp'.
Sublime Chord finds a base class, adds that base class' class levels to Sublime Chord levels, adds any randumb CL modifiers (Orange Ioun Stone, Green Star Adept) then sets every arcane CL the character has to that number, including it's own. It's not adding or involving CLs at all, just class level + class level + magic items or spells or whatever. Prestige classes that say '+1 spellcaster level' that apply to sublime chord count, but not those that apply to the class it is adding to itself.
Knight of the Weave doesn't do any of that, it just finds all the CLs around, adds them together, and uses that as it's own CL.
Master Spellthief doesn't ever modify any CLs. It just adds all existing CLs together to get a number used AS the CL for casting arcane spells. It doesn't actually change the actual CLs the classes have, just the number you use to cast spells.
'Effective caster level' is mostly the same as 'caster level' since you use it for anything involving caster level.
You do all of these transformations only once, in whatever order you like, but you can't just have them feeding back into each other forever due to the way they're written.
If one of these guys with Sublime Chord or Knight of the Weave picked up an Orange Ioun Stone, it would increment all their numbers and therefore change Sublime Chord's CL or Knight of the Weave's CL. You'd go back to the start and apply all the bonuses again, but this time including the Orange Ioun Stone, in whatever order was most advantageous to you as normal. So you'd undo the transformations and go from the top, work it all out again but with the new factor. Same if you gain a level, etc.
Best Answer
Bottom line up front: Skald. Plenty of other classes are more powerful, even without all-18s compared to an all-18 skald, but I don’t think any other class is quite so happy to see all-18s.
To begin with, spellcasters are powerful independently of their MAD; being SAD is just one of many things they have going for them. So even with all 18s, even though they really don’t need it, spellcasters are still the most powerful. I think you grasped this, but just to be clear and for completion’s sake.
Moreover, note that rolling all 18s does not solve MAD problems – for a truly MAD class, at mid-to-high levels the impossibility of magically improving all of those ability scores at the rate a SAD class would, means that SAD is still far superior. This is particularly true in Pathfinder, as opposed to 3.5, because Paizo decided to shaft MAD classes even harder by moving all enhancement bonuses to physical ability scores into items that take the same item slot (belt), and all enhancement bonuses to mental ability scores into items that take another item slot (headband). If you need more than one physical score, or more than one mental score, you are going to be paying more than double what a SAD class would.
So this is less “what is the best class with all-18s” (the answer to that is the same as it would be with only one score in the 16-18 range), and more “what class does all-18s let me play that would otherwise suffer too much MAD?” Furthermore, this answer is going to restrict itself to discussing low-to-low-mid levels (say, up to about 9-10 at most), since the benefit of all-18s wanes as you get into higher levels.
Cleric and Druid
Just, to mention them: they’re super-powerful, they like Strength and Constitution pretty well, in addition to Wisdom, and the cleric certainly doesn’t mind Charisma. They kind of qualify, except that they can get by on just Wisdom if they have to.
Qinggong Monk
The monk unchained gets a lot of nice things that came from qinggong monk. I haven’t seen one in play yet, but it should be comparable for this purpose.
Monk certainly is MAD, but that’s just one of its many failings. Even with all-18s, the core monk struggles mightily.
That said, the qinggong monk is a mini-spellcaster, which still has the monk’s need for Strength, Dexterity, and Constitution. Having 18s in all of those stats definitely allows a qinggong monk to make better use of his or her physical options, while retaining spellcasting ability. Sadly, the lack of any good way to work the magus’s Spell Combat or Spellstrike abilities limits the ability to fuse the two neatly.
Magus
Which leads us nicely into the magus itself. While definitely a few steps down from a fullcaster, the magus is reasonably fun and as a physical+magical class, makes good use of Strength (or Dexterity, if Weapon Finesse), Constitution, and Intelligence. Obviously, Dexterity and Wisdom have their uses for everyone, so having a high score in those is nice. Without Perception as a class skill, Wisdom 18 just about counteracts the loss of the +3 class skill bonus, which helps avoid surprise. The high Charisma falls a bit flat, but magi have Use Magic Device in-class, so you effectively start with a +7 or +8 to that compared to a warrior who dumped Charisma and did not have it.
Bloodrager
With caveat that I have only read the class, never played it or seen it played.
Again following the trend of the physical+magical classes, the bloodrager has the neat ability to automatically apply a spell to himself when he starts a bloodrage. That’s nifty. The class also wants substantial Strength, Constitution, and Charisma, which puts a lot of those 18s to use. Again, Dexterity and Wisdom are some of the better scores for their general use without specific class features, and Intelligence is nice enough for the skill points.
That said, the spells are few and weak, and the ability to auto-cast them on rage comes late (11th for 2nd-level-and-lower spells, 20th for any spell). This is a fairly solid idea for a class but the limits placed on it are just far too tight. A bard progression rather than paladin progression, with the auto-casting coming online from the beginning and not limiting the level of spell used, is what this class needed.
Skald
I bet you didn’t see this coming. Doesn’t have the unique bloodrage auto-cast thing that the bloodrager does, but the skald is basically a bard with better armor and weapon proficiencies, and a more combative bent to its music.
Better, the skald really would like to put Strength, Dexterity, Constitution, Intelligence, and Charisma to good use. Going first is particularly important for the skald, because you want your music bonuses to be in effect ASAP, the skald can do melee quite well, and the spells and music depend on Charisma.
I have not gotten an opportunity to play with most of the unchained classes or hybrid classes. Hybrid rules, in particular, make likely targets here, since classes that combine magic with martial ability are likely to risk MADness.
Also, the Path of War material from third-party publisher Dreamscarred Press is excellent, and each of those classes needs a minimum of three ability scores (Strength-or-Dexterity, Constitution, and one mental score). The design there is tighter than Pathfinder’s typical fare, and in particular they do take some steps to limit the problems of MADness, but they still benefit quite a bit from high scores all around.