Just like the PC's target the enemy spellcasters first. If so much of the character's resources have gone to AC, he's unlikely to be the high damage team member, so ignoring him to focus on the softer targets with higher damage potential makes sense. It is what the PC team would do, so why should NPC's be tactically stupider? Once the others are out of the way, teamwork like Aid Another against this guy becomes much more practical.
There are an array of abilities against which armor is less useful, as already cited by others.
Ultimately, I would WANT this PC to feel awesome in his defensive ability pretty regularly. If he had instead focused all his character resources on higher damage, he'd get to be the guy who cleaves through the opponents before they even get an attack and feel Awesome. He spent his resources on defense, so he should be Awesomely defended.
At 8th level, these guys should feel pretty powerful, so having town guards be a limited threat really doesn't bother me. If they're abusing that power, the town would logically take the same approach most game worlds do - hire some heroic adventurers to deal with these powerful brigands!
To start, maybe you need your scenarios to feature more investigation and NPC interaction. That seems highly likely to be this guy's weak point, since everything he has is combat-focused. Let the PC's who invested resources in non-combat abilities shine there, and he can shine in combat.
With Combat Expertise, he's taking a stiff penalty on attack bonuses to get defense bonuses. I always thought of Combat Expertise as a replacement for Fighting Defensively, but I see nothing in the rules that prevents using both. That's a -7 penalty to hit, though (-3 from Expertise and -4 from Defensive Fighting). Why not throw in some high AC opponents and make him reconsider those bonuses? I assume he's not getting much mileage from iterative attacks.
So it's low magic when the player wants to complain about his weaknesses coming into play, but not when he wants to commission a very specific item for his character. Somehow, that sounds less than fully reasonable. Especially if the characters' power has also come with some fame. If enemies know this guy is almost unhittable in combat, but easily affected by mind-affecting spells, they would be pretty stupid not to hire someone who can target his weaknesses - and you've established spellcasters aren't tough to hire, right?
Hey, if he wants a bonus to Will saves, all he has to do is Rage...and suck up the AC drawbacks. I'd also suggest this organization they are up against should have an idea of the characters' capabilities (not just his PC) and the ability to equip their minions in an equally focused manner. So maybe they should start sending in, say, some Net and Trident warriors to oppose this guy. No reason they can't have feats to enhance attack bonuses with their nets. His Touch AC is pretty good, but removal of armor and shield bonuses drops him to a much more hittable range.
Net fighters staying 10' away, probably with decent AC's so he has to choose between a decent touch AC and a decent chance of hitting them (Defensive and CE being a much bigger part of his Touch AC) changes the game a bit, I suspect.
You have some good points. Although I'm already doing some of these things, and the player is considering changing his character because of it. My missions have been mostly investigation combined with combat - about 50% each. As for CE+FD, he seldom uses this anymore, and he used to routinely miss enemies at the lower level because of his extreme cautiousness.
I think you misunderstood something about my campaign - spellcasters are not dime a dozen. Only major organizations can even hope to bring in several spellcasters, and the party is working for the government of the most powerful empire in that game world. The spellcasters they have met so far has been from an opposing city-state which is almost unique in the world by having an actual school of magic (the Empire doesn't).
Also, most spellcasters are of the non-adventuring type in my games. It doesen't make sense to send such a rare resource out to die when they can stay in base and do valuable magical research, scrying, long-range communications, item crafting for operatives etc. Also the party's spellcasters are putting their time in as well, crafting items for NPCs when asked for no additional price.
In every major encounter the... enemy spellcasters are there to mess up the party.
The character has been dominated once (for several days, killed a party member), Held 2-3 times, blinded 3 times (glitterdust), Feared 3 times.. probably more I forget. Many of his enemies have realized he has this weakness, but his party has helped him out every time.
I am curious in what you and your players want to do with the campaign. Looking at the current state of it, it doesn't look like it's very viable.
When I mentioned core, I was thinking of 3.5 (I am not familiar with pathfinder specifics) and to me that was the PHB. Might you think of core as a wider variety of books or is pathfind really that broken?
Anyway, the question isn't really what you can do, bute more of a question of what you and your players want to do with the Campaign. We usually discuss things like this before creating characters. Sometimes we go for "go as broken as you want" and sometimes we go for "avoid powergaming too hard". Where are you and your players in this?
My players do know when they have found a combination that's good enough to "break" the game and because of the social contract we have they either approach me with it or just don't use the loophole.
Like the player who found the "Blinding spittle" spell gave a +4 ranged touch attack to blind the foe until he managed to wash it out. I let him use it if just used it occationally and agreed that it wouldn't work against dragons and such.
The campaign is far from broken, I just miss having lower level enemies to be a somewhat reasonable threat. Even Conan gets taken down when faced with overwhelming numbers.
Pathfinder isn't broken, but it makes more powerful characters than 3.5 generally speaking. In the case of AC PF easily gives 2-3 more points from boosted armors and feats, but lacks the outrageous balance issues in some 3.5 material.
Power gaming: The group isn't bad on this is general, and actually I was surprised as that one player generally makes far less effective characters - his last character in PF was a completely useless cleric/wizard.
No, I didn't break the game. I made ONE defense (out of FOUR) impossible for him to hit using perfectly legal game elements he allowed.
He broke the game by not using his brain and thinking "Wow, he's got a weak Will, Reflex, and Fortitude. Which of those three should I attack, instead of focusing on his strongest point?"
Maybe I have high standards, but I expect more from a DM.
You really think AC is the same as the saves? This isn't 4th edition. AC is what is attacked by at least 80% of the enemies, and is also far easier to get high. You're basically saying that the DM is only allowed to use spellcasters or monsters with SPA's against the group because you somehow managed to make a character that has a completely overpowered AC? If the game system allows broken combos, don't blame the DM when you abuse that fact.
