While I am philosophically opposed to making monster classes that sort-of-but-not-really duplicate the monster (if you're playing a CK, play one, not an almost-CK), the class isn't as unbalanced as it might appear. It looks like the player or DM are mistaken on a few points.
- And the CK has been wielding a +2 Holy, Unholy, Lawful, Chaos - Greatsword, since level 4.
He shouldn't have had that, exactly. Looking at the ability description, at 4th level, it's only a +1 weapon, and it deals +1d6 damage to NG, LN, CN, and NE people and +2d6 damage to LG, CG, LE, and CE people. It shouldn't have advanced to a +2 / 2d6 vs. neutrals / 4d6 vs. non-neutrals until last level, so if your group interpreted that as a
+1 holy unholy axiomatic anarchic greatsword since level 4 he's been dealing too much damage.
- Has the ability to fly since level 6
Full casters first gain access to
fly at 5th, and warlocks gain constant flight with
fell flight at 6th level. That's not out of line power-wise.
- He has been large since level 8
You can get Powerful Build at level 1 with half-giant or goliath, and methods to grow larger (such as
enlarge person) are available then too.
- Level 9 teleport, wall of force, 3 times per day AND Arcane Sight is in a constant effect on him.
3
teleports and 3
walls of force at 9th level is in line with what a full caster can do at about that level (a focused specialist could do that at 9th, a sorcerer at 10th). In fact, most of the SLAs are on-level compared to a full caster, but more limited in scope, with the lower-level ones increasing in frequency as you level.
- OH and I love the fact that he can cast magic missile with caster level 10 at HD/level 1
Not quite. The "no limit of missiles based on CL" means there's no cap,
not that he casts at CL 10. He has 1 missile at level 1, 2 at level 3, etc. as normal, but he can keep gaining missiles as long as he wants after the cap would normally kick in.
So it seems that part of the issue here is misinterpreting the sword and MM damage for a while, and part of it is not realizing what a full caster can do at the same levels.
In fact, a cleric or archivist could be built to duplicate everything here (or at least mimic it pretty closely) at once except Know Enemy (which you can kinda do with Sense Motive or Urban Savant), Worthy Enemy (which you can kinda do with Mark of Cania), and Spoils of War (which you can kinda do with an artificer). So you could think of this as a set of ACFs for a cleric or archivist, and it would come out pretty much the same.
In fact, the imbalance looks like it's mostly coming from the other party members. A 9th level sorcerer/wizard, unless it's actually a wizard 4/sorcerer 1/ultimate magus 4, is
far behind where he should be as a full caster at this level, and a monk/fighter is just underwhelming in general without a bunch of monk ACFs and a good PrC. This isn't to say that it's okay that he's playing this class in an unoptimized party--rather, it is his job as an optimizer and a good player to fit his character to the average party power level as best he can--but it's not the class itself that's overpowered, it's the contrast between it and the other two characters. In a party of this CK, wizard/PrC, and cleric/PrC, he'd fit right in.
So if I were you, I'd suggest to the DM that he make something a little more on par with the rest of the party, either by retiring this character and picking up a different, weaker monster class (I like hound archons and lumis for something that screams "outsider" but isn't too powerful) or by coming up with an in-game reason for his character to be de-powered and building a character that's thematically similar (a mystic ranger would be a good choice, since it has plenty of magical power and some combat power, but is much more limited than a cleric or wizard).
