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... because it is and yet it isn't.
From a purely symmetrical perspective, the two feats could be made on the same model. They kinda are, the the bonus ratio is different. Also, Combat expertise is an improved version of the 'fighting on the defensive' option. There are not basic option to Power Attack (which can be later improved with a feat).
Power attack also has three different 'levels' of use, depending on whether the attacker is using a light, a 1-handed or 2 handed weapon. The parallel would be easy to do with no-shield, light shield and heavy shield.
So basing Combat Expertise on the text from Power Attack, we would get something like this:
You can use your shield and weapons to increase your defense at the expense of your accuracy.
Prerequisite: Int 13.
Benefit: When wielding a buckler, a light shield or a weapon granting a shield bonus to AC, you can choose to take a –1 penalty on all melee attack rolls and combat maneuver checks to gain a +2 dodge bonus on your Armor Class.
This bonus to AC is increased by half (+50%) if you are wielding a heavy shield. This bonus to AC is halved (–50%) if you are not wielding any shield or weapon granting a shield bonus to AC. When your base attack bonus reaches +4, and every 4 points thereafter, the penalty increases by –1 and the bonus to damage increases by +2. You must choose to use this feat before making an attack roll, and its effects last until your next turn.
Obviously this would benefit the shield-user the most, which are often those who go for the biggest armor and therefore benefit from a decent AC already. But since those character also rely on Power Attack for massive damage, it becomes a strategic choice; hit hard or be hard to hit.
This version would also encourage the use of the buckler (for more roguish characters), which I don't see much use around game tables otherwise.
comments?
'findel
I definitely agree the existing Combat Expertise is the red-headed stepchild of the combat trade-off feats. I question the penalty to no-shield wielders, though--what about free-hand fighter types?
I'm on the fence overall...which means you've probably got this spot on. It's much more appealing than the existing feat, anyway. Personally, I've just scrapped defensive fighting altogether, in favor of the feat, but I think I may like this form of it over mine.
I question the penalty to no-shield wielders, though--what about free-hand fighter types?
While the text points at a penalty, I simply added benefits to shield wielders compared to RaW combat expertise (which at the moment only grant the 'no-shield' option).
As for free-hand fighters, they exist as a fantasy archetype but don't make much sense from a fighter's perspective. Historically, warriors always made use of both of their hands, either using a two-handed weapon (or a 1-handed weapon two handed) or held something in both hands (either a shield or a secondary weapon).
There are fighting styles where one hand is tucked behind one's back and the body is turned sideways to offer less surface to hit (think Errol Flynn's Robin Hood) . In game term, I'd consider that a feat; something that grants a +1 shield bonus to AC while not wearing any shield (and therefore qualifying for better use of Combat Expertise).
Same goes for knife/brawling/dirty fighting techniques where one hand is kept free to grab, deflect and catch things. These would be the result of a feat which can be specified to qualify for CE).
Historically, things get a bit different as riffles and pistols get more common - making the shield obsolete anyways - but in my opinion, Pathfinder RPG recreates an era where pistols have not yet dethroned armors and the use of melee weapons.
So other than melee-casters who need a free hand to cast spells and situations where carrying a shield is too cumbersome or impractical, I don't see why an adventurer should enter a fight with a free, unused hand.
'findel
Okay, you've convinced me. You've clearly thought quite a bit about this! Now I want to go design said feats...so many ideas, such little time...
I don't like anything that gives sword and board more AC. Other forms of defense are fine, like extending it to adjacent characters, applying it to touch AC or possibly reducing the ability of foes to critically hit you, but shield wearers already have a +7 advantage over other ACs around 12th level, and that's too much of a gap. In a mixed party, it becomes either impossible to hit the shield user, or a foregone conclusion that one will hit the non-shield user. This is before the character begins to focus their shield in feats or such, gaining even more AC advantage. Two weapon fighting and a shield enchanted as a +5 weapon of defending provides even more craziness.
I think combat expertise already provides a good bonus and doesn't need alteration.
I don't like anything that gives sword and board more AC. Other forms of defense are fine, like extending it to adjacent characters, applying it to touch AC or possibly reducing the ability of foes to critically hit you, but shield wearers already have a +7 advantage over other ACs around 12th level...
While I don't agree that Combat Expertise is a particularly good feat by RaW, I see the reasons given above. That includes a significant investment in the character's shield however, but I understand how things can get min-maxed out of control.
As for the disparity between shield user's and non-shield users AC, the shield has got to bring a comparable advantage to the damage output given from two-handed fighters and two weapons users. But as Pathfinder already brings shields as a source of damage in its own, you might be right about this being over the top. At 20th level, a fighter/paladin/ranger would get a additional +15 to AC for a -5 to hit! Would the inability to use Power Attack enough of a penalty to weight out the bonus to AC? Perhaps not...
Perhaps I got the whole thing backward, whereas Combat expertise should particularly benefit the free-handed, unarmored fighter?
'findel
How about basing it on the type of armor worn? This does turn it into a more Dex-based, Dodge-like feat, and might require moving some feats and prerequisites around, but...1-3 conversion for light or no armor, 1-2 for medium armor, and 1-1 for heavy armor, representing parries and dodges which detract from your attacks.
That also helps make the lightly-armored fighter feasible, though still lower in AC than a heavily armored one.
How about basing it on the type of armor worn? This does turn it into a more Dex-based, Dodge-like feat, and might require moving some feats and prerequisites around, but...1-3 conversion for light or no armor, 1-2 for medium armor, and 1-1 for heavy armor, representing parries and dodges which detract from your attacks.
That also helps make the lightly-armored fighter feasible, though still lower in AC than a heavily armored one.
You can increase your defense at the expense of your accuracy.
Prerequisite: Int 13.
Benefit: You can choose to take a –1 penalty on all melee attack rolls and combat maneuver checks to gain a +2 dodge bonus on your Armor Class.
This bonus to AC is increased by half (+50%) if you are wearing a light armor or no armor. This bonus to AC is halved (–50%) if you are wearing a heavy armor. When your base attack bonus reaches +4, and every 4 points thereafter, the penalty increases by –1 and the bonus to damage increases by +2. You must choose to use this feat before making an attack roll, and its effects last until your next turn.
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I can smell cheese from the +5 mithral chainshirt + Combat Expertise sneak attacking rogue...
Much better overall. Though...at the highest levels, someone with light armor can get a higher AC than someone in heavy armor by using it. On the other hand...they did spend a feat, and it's only a few points of AC, so maybe it's balanced.
Something to keep in mind, (and correct me if I'm wrong) is that Combat Expertise can be stacked with fighting defensively. It's not either or. Which means that you can get the combat expertise bonus plus the defensive bonus. This gives an additional penalty, but a larger AC.
There is no similar mechanic for Power Attack.
Also, it is possible to achieve truly frustrating ACs even without your feat modification. There's a paladin in my group that is nearly invulnerable, all through standard methods. Perhaps at higher levels, your modification might be useful (where max available ACs top out), but it's ripe for overuse.
Much better overall. Though...at the highest levels, someone with light armor can get a higher AC than someone in heavy armor by using it. On the other hand...they did spend a feat, and it's only a few points of AC, so maybe it's balanced.
A +5 full plate is AC 24 (Dex not factored in)
A +5 chainshirt plus Combat Expertise at level 4th would be AC 25 (-2 attack, much higher allowed Dex modifier, even more so if mithral)So this Combat Expertise would allow a lightly armored fighter to out-AC a heavy armored fighter at level 4th.
The question is whether the inability to perform Power Attack in addition is enough of a penalty to worth the unbalance?
I'm not convinced this is a good idea...
Perhaps move it down a step? 3-1 for unarmored, 2-1 for light, 1-1 for medium and heavy?
... because it is and yet it isn't.
From a purely symmetrical perspective, the two feats could be made on the same model. They kinda are, the the bonus ratio is different. Also, Combat expertise is an improved version of the 'fighting on the defensive' option. There are not basic option to Power Attack (which can be later improved with a feat).
Power attack also has three different 'levels' of use, depending on whether the attacker is using a light, a 1-handed or 2 handed weapon. The parallel would be easy to do with no-shield, light shield and heavy shield.
So basing Combat Expertise on the text from Power Attack, we would get something like this:
You can use your shield and weapons to increase your defense at the expense of your accuracy.
Prerequisite: Int 13.
Benefit: When wielding a buckler, a light shield or a weapon granting a shield bonus to AC, you can choose to take a –1 penalty on all melee attack rolls and combat maneuver checks to gain a +2 dodge bonus on your Armor Class.
This bonus to AC is increased by half (+50%) if you are wielding a heavy shield. This bonus to AC is halved (–50%) if you are not wielding any shield or weapon granting a shield bonus to AC. When your base attack bonus reaches +4, and every 4 points thereafter, the penalty increases by –1 and the bonus to damage increases by +2. You must choose to use this feat before making an attack roll, and its effects last until your next turn.
Obviously this would benefit the shield-user the most, which are often those who go for the biggest armor and therefore benefit from a decent AC already. But since those character also rely on Power Attack for massive damage, it becomes a strategic choice; hit hard or be hard to hit.
This version would also encourage the use of the buckler (for more roguish characters), which I don't see much use around game tables otherwise.
comments?
'findel
I like it very much - but leave Combat Expertise as it is and call this feat 'Shield Expertise' or some such and drop the lower tier of benefit.
Comparing it to +5 armor at 4th level is silly. That's why I said 12th level, that's the level when you can get a +5 shield without taxing your wealth.
You can increase your defense at the expense of your accuracy.
Prerequisite: Int 13.
Benefit: You can choose to take a –1 penalty on all melee attack rolls and combat maneuver checks to gain a +2 dodge bonus on your Armor Class.
This bonus to AC is increased by half (+50%) if you are wearing a light armor or no armor. This bonus to AC is halved (–50%) if you are wearing a heavy armor. When your base attack bonus reaches +4, and every 4 points thereafter, the penalty increases by –1 and the bonus to damage increases by +2. You must choose to use this feat before making an attack roll, and its effects last until your next turn.
At 4th level, character wealth is 10,500 gp. That means any given item ought to be under 2,625 gp.
+1 full plate = 2,650 gp.
+2 chain shirt = 4,250 gp. (too much)
+1 chain shirt = 1,250 gp.
and for completeness sake, we'll throw in a breastplate guy as well.
+1 breastplate = 1,350 gp.
Now, because our medium and light fighter spent a bit less on their protection, we'll give them a ring of protection to make up the difference. It pushes them a bit higher than the heavy in terms of cash spent, but it's a fair assumption.
Lets assume a heavy fighter focuses on Str and Con, and a light fighter focuses on Dex and Str. Our medium will focus on Str and Dex.
Heavy 18 Str, 13 Dex, 14 Con, 13 Int, 8 Wis, 12 Cha
Medium 18 Str, 14 Dex, 13 Con, 13 Int, 8 Wis, 12 Cha
Light 14 Str, 18 Dex, 13 Con, 13 Int, 8 Wis, 12 Cha
The full plate fighter has AC 23 (+10 armor, +1 Dex)
The breastplate fighter has AC 20 (+7 armor, +1 deflection, +2 Dex)
The chain shirt fighter has AC 20 (+5 armor, +1 deflection, +4 Dex)
With Expertise at 4th level, the full plate fighter gets +2 AC/-2 atk (AC 25)
The breastplate fighter gets +4 AC/-2 atk. (AC 24)
The chain shirt fighter gets +6 AC/-2 atk. (AC 26)
Now, 20th level fighter. Money is no object. We'll allow for +5 inherent bonuses to all physical stats. Note all ACs drop into the high 30s without shield.
Heavy +5 full plate, +5 amulet of natural armor, +5 ring of protection, +5 heavy shield, +6 belt of physical perfection. AC 46 (+14 armor, +5 deflection, +5 Dex, +5 natural, +7 shield)
Medium +5 breastplate, +5 amulet of natural armor, +5 ring of protection, +5 heavy shield, +6 belt of physical perfection. AC 45 (+11 armor, +5 deflection, +7 Dex, +5 natural, +7 shield)
Light +5 mithral chain shirt, +5 amulet of natural armor, +5 ring of protection, +5 buckler, +6 belt of physical perfection. AC 45 (+9 armor, +5 deflection, +10 Dex, +5 natural, +6 shield)
With Expertise at 20th level, the full plate fighter gets +6 AC/-6 atk (AC 52)
The breastplate fighter gets +12 AC/-6 atk. (AC 57)
The chain shirt fighter gets +18 AC/-6 atk. (AC 63)
As you can see, your feat causes ACs to be wildly inflated at 20th level, to the point where no monster of CR 17-25 can even hit them without a natural 20. Even without shields, the ACs are 45/50/57. That's too high, and that's why Combat Expertise doesn't allow a -1/+2.
Allowing it to offer light armored warriors a -1/+2 and leaving it as is for heavy and medium warriors wouldn't be terrible. Fighter ACs are already sick.
Comparing it to +5 armor at 4th level is silly.
Yes, it is.
It was only to show that the difference between chain shirt and full plate (given the same enhancement bonus) is merely a +5 armour bonus to AC.
At 4th level, a lightly armoured fighter using this CE would gain a +6 dodge bonus to AC, while the heavy armoured fighter a +2 dodge bonus to AC. That's a difference of +4, which almost fills the gap between chainshirt and full plate, not considering all the higher Dex modifier cap and other advantages that light armour gives you. At 4th level!
Hence my closing statement:
I'm not convinced this is a good idea...
I still like my first Combat Expertise re-write based on the use of shield; I never like the fact that a +1 enhancement on a light shield improved its efficiency by 100% regardless of the character's level. It's like saying that a +1 short sword deals 2d6 instead of 1d6+1, or that a character's BAB caps at +1...
I know that D&D is an abstract model, but I never like the fact that an object that was considered essential in real life is merely a trivial accessory in D&D (enhancement bonus notwithstanding).
However, I agree that this version of CE would work better in a low-magic setting or in a game less dependent on magical enhancement.
'findel
i disagree; AC bonus is much better than a damage bonus.
what I don't agree with is the feat's 13 int requirement
It's not the 13 Int req that you should fight against, it's the fact that 15 point buy is the standard and that you don't feel useful if you raise Int to 13.
I personally have played fighters with Combat Expertise and have found them to be quite enjoyable. Min-Maxing does help but is not required to play a flavorful and fun character.
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LOL! my current Pathfinder Society character is a Fighter 7 with the Taldan Rondelero archetype, and yes, he has combat expertise. So, yeah, I can find characters with that feat enjoyable, thank you.
Min-maxing is not my bread and butter. I like to plan my character progression well ahead but that's about it.
I have played in 15 point buy campaign quite a few times and had nothing against it.
No. My problem (and I'm not the only one if I judge it from the various threads on the matter) is that you're asking a fighter to be of Int 13 in order to access the feats that make him better at tripping, disarming, etc.
When was the last time you saw a Metamagic feat with a STR 13 requirement?
LOL! my current Pathfinder Society character is a Fighter 7 with the Taldan Rondelero archetype, and yes, he has combat expertise. So, yeah, I can find characters with that feat enjoyable, thank you.
Min-maxing is not my bread and butter. I like to plan my character progression well ahead but that's about it.
I have played in 15 point buy campaign quite a few times and had nothing against it.
No. My problem (and I'm not the only one if I judge it from the various threads on the matter) is that you're asking a fighter to be of Int 13 in order to access the feats that make him better at tripping, disarming, etc.
When was the last time you saw a Metamagic feat with a STR 13 requirement?
So you're not against the pre-requisites of the Combat Expertise feat.. you're against the pre-requisites of the Improved Trip, Improved Disarm, etc feats.. That's something completely different. :P
In regards to Improved Trip/Disarm/Etc..
I've always felt that Combat Expertise is a good all around feat to have as a pre-requisite for the improved maneuver feats.. however, as a GM I usually houserule that Weapon Focus is enough of a pre-requisite for those feats.. I however only give them the bonuses when they are wielding the weapon they have a focus in. That however, is a houserule. :P
Back on Topic..
You can use your shield and weapons to increase your defense at the expense of your accuracy.
Prerequisite: Int 13.
Benefit: When wielding a buckler, a light shield or a weapon granting a shield bonus to AC, you can choose to take a –1 penalty on all melee attack rolls and combat maneuver checks to gain a +2 dodge bonus on your Armor Class.
This bonus to AC is increased by half (+50%) if you are wielding a heavy shield. This bonus to AC is halved (–50%) if you are not wielding any shield or weapon granting a shield bonus to AC. When your base attack bonus reaches +4, and every 4 points thereafter, the penalty increases by –1 and the bonus to AC increases by +2. You must choose to use this feat before making an attack roll, and its effects last until your next turn.
Would a Rogue that has TWF and TWD that get a +1 Shield AC bonus from their offhand weapon.. be able to treat the Combat Expertise as if wielding a buckler? :)
Also.. would it increase CMD while lowering CMB?
Would a Rogue that has TWF and TWD that get a +1 Shield AC bonus from their offhand weapon.. be able to treat the Combat Expertise as if wielding a buckler? :)
Yes, that would be the idea.
Also.. would it increase CMD while lowering CMB?
Haven't thought about CMD, but...
A creature can also add any circumstance, deflection, dodge, insight, luck, morale, profane, and sacred bonuses to AC to its CMD.
So I'd say yes it would
'findel
'findel
That's pretty rad, I support this change. :)
I've always subscribed to the belief that AC is better than HP (better to never take damage than to be able to take a lot of it), and winning a fight means you're still alive at the end. AC is better than damage, IMO, hence the disparity between CE and PA.
My opinions on AC have never been popular in my groups, though I must say that I've never had a character die in combat to date.
TL;DR: Combat Expertise is fine.
I've always subscribed to the belief that AC is better than HP (better to never take damage than to be able to take a lot of it), and winning a fight means you're still alive at the end. AC is better than damage, IMO, hence the disparity between CE and PA.
My opinions on AC have never been popular in my groups, though I must say that I've never had a character die in combat to date.
TL;DR: Combat Expertise is fine.
To play devil's advocate:
The best defense is frequently a good offense. Better still to cut someone down before they can even swing their sword. Each round an enemy survives is a round they have a chance to hurt you, or your friends.
Self-evidently, winning a fight doesn't just mean 'being alive'. The orc who fled from the slaughter of his warband is alive, but he clearly didn't win.
Consider the hypothetical case of someone who has an AC so high that any given opponent can only hit them on a natural 20. They are virtually invulnerable in combat. But if they only do 1 damage, and hit rarely themselves, they're no threat to anything, and could certainly never 'win' a fight.
All that said...I would probably have torn my hair out if the Paladin in my CotCT game was using this. He really didn't need any more AC...
All that said...I would probably have torn my hair out if the Paladin in my CotCT game was using this. He really didn't need any more AC...
By curiosity, was that paladin making use of Power Attack? If so, did it have a significant impact on its damage output?
No he used regular Combat Expertise with a solid shield; damage--and an even further boost to AC--came from Smite Evil. Plus the fact that he was wielding a bastard sword. The Falchion wielding barbarian did more damage, but the paladin did a respectable amount, bypassing all damage reduction, all while being virtually untouchable. Especially with a ring of Evasion.
No he used regular Combat Expertise with a solid shield; damage--and an even further boost to AC--came from Smite Evil. Plus the fact that he was wielding a bastard sword. The Falchion wielding barbarian did more damage, but the paladin did a respectable amount, bypassing all damage reduction, all while being virtually untouchable. Especially with a ring of Evasion.
Right, I'm not used to Pathfinder's new Smite Evil yet...
It indeed makes the Paladin much less dependent on external source of damage (feat or equipment) to be viable in combat.
'findel
Laurel,
Good attempt at fixing CE. While I do believe your version is an improvement, I think the PF rules lend themselves to the philosophy of "offense is king". It's almost never worth it to sacrifice offense for defense in the PF system. So, CE will never be a good feat, regardless of its mechanics. Your version is certainly better though, good effort.
The whole "offense is king" philosophy is part of the reason why sword and board Fighters are so unpopular; the extra AC from a shield is almost never worth the loss of damage output.
That is one of the things I don't like about PF. It's my opinion that defense should be just as important as offense in a well-balanced game system. Unfortunately I just don't think that's the case in PF.
I know that D&D is an abstract model, but I never like the fact that an object that was considered essential in real life is merely a trivial accessory in D&D
Don't forget that in real life a shield did become trivial because of advancements in armor technology. Armor technology that exists in Dnd.
That said, on your feat: I think that in general, a point of attack or AC being roughly equivalent to two points of damage or DR is a pretty basic game assumption. You see this in most every basic feat for physical combat - Weapon Focus = +1 to hit, Shield Focus = +1 AC, Weapon Specialization = +2 damage, all for the price of one feat. Power Attacking is +2 per -1.
It's not entirely correct only in that, as someone else said, defense isn't as useful as offense when all values are fairly near normal expected values for the level, so AC isn't as useful as attack bonuses as a general rule. But the disparity isn't so great as to be 2 to 1. More like 4 to 3 or at most 3 to 2.
And it's not a universal rule either. If the modifiers start swamping the range of a d20, it no longer holds. +12 AC for combat expertising is big enough to swamp the range of a d20 (hitting you 50-50 goes to hitting you 5-95) and, therefore, too big.
Don't forget that in real life a shield did become trivial because of advancements in armor technology. Armor technology that exists in Dnd.
Shield lost their use in the military for many reasons - mainly about firearms making both shield and armours obsolete - but I still believe that the era which Pathfinder represents (as far as real-life analogies can go) is one where technologies have not yet surpassed the use of shield.
True, there are armors in Pathfinder that are better than their 14th century counterparts, but even low-tech armours in Pathfinder are superior to a large shield (studded leather > heavy shield). Especially in a world where dragons spit fire and wizard toss fireballs, a shield's got to be a fighter's best friend...
But I better understand the 2-1 ratio in favour of damage that the system applies universally in its rules, thanks to your post.
That actually gives me a lot to think about...
'findel
I houserule it that if you are not using a shield, the feat works as written. If you are using a shield, the bonus to AC is doubled. It seems to encourage using a shield quite a bit rather than two handed weapon or duel wielding.
Something that came to my mind recently.. What about stating Wisdom 13+, instead of Intelligence 13+, as prerequisite for Combat Expertise?
Be careful. +1 AC is worth a lot more than +1 damage, so efforts to equate the two in the name of symmetry are based on something of a false premise.
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...to gain a +2 dodge bonus on your Armor Class.
I have to agree with Coriat and Kirth. I think it's a mistake to think that damage and AC are of equivalent value. Combat Expertise trades 1 for 1 because +1 to hit is the same value as +1 to armor class, while Power Attack trades 2 for 1 because damage is worth less than to hit or AC.
Sure, Combat Expertise, taken alone and naked, is a poor excuse for a feat. However, it's an awesome feat for a character with an optimised AC. +1 AC doesn't help you much if the BBEG can only miss you on a natural 1, but if he can only hit you on a natural 19, this +1 to AC (or more) will make you 100% harder to hit. That's why I think it should remain as it is.
Have abandoned this idea.
Indeed in the present iteration of the game, 1 AC = 1 to hit = 2 damage. Power Attack and Combat Expertise both have their proper exchange rate.
I'm still left with a feeling that shield isn't represented in the system as it *should* (<-- personal opinion here, don't climb on your high horses). Partially blaming the shield issue on the system's dependency on magical enhancement.
I'm keeping the concept to have PA and CE work on the same principle for my homebrew system, which plays on slightly different basic mathematical assumptions.
Thanks for the input everyone
'findel
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I'm still left with a feeling that shield isn't represented in the system as it *should* (<-- personal opinion here, don't climb on your high horses). Partially blaming the shield issue on the system's dependency on magical enhancement.
Its also a consequence of D&D never modelling parrying except as an abstraction. You really need parrying rules for shields to shine, as they are parrying machines.
Have abandoned this idea.
Maybe there's no need to abandon the idea... Consider granting the -1 attack/+2 AC bonus exchange when:
a) you're wearing a shield, or;b) you're wearing light armor or no armor and a one-handed weapon in one hand.
About the first situation, it would be arguable if the Two-Weapon Defense feat qualifies for the improved benefit. Maybe it should, since two-weapon fighting is now a quite poor option of combat style.
I like the idea of granting an increased bonus to shield users.
My big beef in this area of the rules is that fighting defensively and all-out defense are weaksauce, and they don't scale at all. +4 AC in exchange for not attacking is awesome at level 1, but just doesn't cut it at level 10. +2 AC for a -4 to hit is a complete joke.
Here are my rewrites:
Fighting defensively -1 to hit plus an additional -1 for every 4 points of BAB. Gain the same amount to AC. Basically, combat expertise is the base default effect.
Combat expertise: add half your Int modifier to you AC when fighting defensively. Add your full int modifier to AC when using all out defense. Makes sense because 13 int is required for combat expertise.
All out defense gives you double your fighting defensively bonus.
Now, I am thinking about letting them add half their shield bonus when fightin defensively(full shield bonus when using all out defense).
So a level 8 fighter with 14 int fighting defensively
Normal -3 to hit, +3 AC
Combat expertise -3 to hit, +4 AC
Heavy Shield +2 -3 to Hit, +5 AC
Shield + Expertise -3 to Hit, +6 AC
Same fighter using all out defense would double the AC gain.