Alternate AC Calculation

[JNAProductions]

All PCs may use 9+Proficiency modifier for their AC, provided they fulfill one or more of the following criteria:

-They are wielding a weapon they have proficiency in
-They are using a shield that they have proficiency in
-They are using a component pouch or focus that they can cast spells with

You may add a shield's AC to this value, as normal. You may NOT use this calculation while wearing armor you are not proficient in.

Additionally, add the following line to the Monk's Martial Arts ability:


-You may use 9+Proficiency modifier for your AC

Finally, add the following line to the Tavern Brawler feat:


-You may use 9+Proficiency modifier for your AC even while unarmed


The idea is pretty simple-PCs get better at defending themselves, even outside of armor, provided they aren't TOTALLY helpless.

If you have a weapon, you can parry and threaten with it, making you harder to hit.
A shield can block, interposing blows enough to get you your AC.
Casting implements allow you to conjure distracting sparkles or momentary barriers of force.

This will, in general, have basically no benefits for players at their best. But, it makes ambushes less lethal for heavy-armored Dexterity-dumpers, and generally provides a bit of safety for all PCs that rely on armor. It's not MUCH, certainly not against worthy opponents, but against, say, a mob of angry farmers? It'll help.

[SpawnOfMorbo]

How about, to simplify things, you just allow people to use their prof bonus (max +5) to replace their dexterity modifier when calculating AC?

Different classes could have their own bonus to this.

Full Casters: Prof Bonus -2
Half Casters: Prof Bonus
Martials (non-casters): Prof Bonus +2

Round down on prof bonus.

Wizard: Would need to rely on dexterity and mage armor.

Paladins/Rangers: Could easily make medium armor builds. Strength based rangers (big axe!) could be a thing.

Rogue: Would have a 16 AC at first level, already doable, but wouldn't have shield prof unless they took a feat. At most 18 AC, which clerics can get via the base rules.

Don't worry about if they are holding a weapon or not, adventurers are awesome like that.

This would work for unarmored defense (barbarian) but a Monk could replace their wisdom modifier with their prof bonus

Heavy armor doesn't rely on dex but since you are so well protected head to toe, you get a bonus of some sort to dexterity saving throws?

This would also allow people to have different ACs and show that classes are different.


Edit: I'm gonna have to add this into some homebrews houserules, I like prof to AC.


Edit 2: I would say make the base AC calculation based on Proficiency and then allow people to replace their Proficiency with dexterity if it's higher.

Then when you have things like unarmored defense you can say 10 + (Prof Bonus) + (Bonus Modifier).

Why put on armors? Bring back damage resistances based on armor, I believe 2e had them.

Light Armor: Full (Prof Bonus)

Medium Armor: (Max Prof: +2, +3 with feat)

Heavy: Prof bonus doesn't matter due to how protective the armor is... Much like how dex works.

[Garfunion]

I agree with your use of proficiency bonus instead of dexterity for calculating AC. I too have pondered the idea. The problem is, those characters that use light/no armor will be at a disadvantage at lower levels. You also reach a point at higher levels that wearing heavier armor is no longer necessary. So armor would need some additional benefits.

No/light armor would need to provide additional AC (maybe a +1 or +2 to its score).
Medium and heavy armor would need additional bonuses. While giving them resistance would be easy, it would offset the more unique defensive class features. I’ve been thinking about giving heavy armor free temporary hit points each round.

[Segev]

If you like the notion of proficiency adding to AC, it would seem the most natural thing to do would be to replace a shield's +2 with instead +proficiency. It's still +2 for lower-level play, but scales with level.

[SpawnOfMorbo]

I agree with your use of proficiency bonus instead of dexterity for calculating AC. I too have pondered the idea. The problem is, those characters that use light/no armor will be at a disadvantage at lower levels. You also reach a point at higher levels that wearing heavier armor is no longer necessary. So armor would need some additional benefits.

No/light armor would need to provide additional AC (maybe a +1 or +2 to its score).
Medium and heavy armor would need additional bonuses. While giving them resistance would be easy, it would offset the more unique defensive class features. I’ve been thinking about giving heavy armor free temporary hit points each round.

I feel like allowing Prof or Dex, whichever is higher (max +5), would solve this issue. If they're going to be in light armor, they know to focus on Dex BUT if they don't focus on Dex they're no totally out of luck. 12 + 2 (prof) is better than 12 - 1 (dex).

Allow for class features to stack or improve armor resistances.

Rogue ability, uncanny dodge, would already stack (heavy armor master is great on a rogue, in a trollish lol way).

Maybe take heavy armor master DR and give it to armors, then have heavy armor master improve on heavy armor DR.


If you like the notion of proficiency adding to AC, it would seem the most natural thing to do would be to replace a shield's +2 with instead +proficiency. It's still +2 for lower-level play, but scales with level.

I actually like allowing shields to work as 1/2 cover. Most of the time cover won't stack barring very special circumstances and even the. It just upgrades to 3/4th or full cover.

Makes a lot of sense with how shields actually work and keeps things simple.

[Amechra]

The Monk rules-tweak is almost entirely pointless - they don't get Martial Arts in any situation where their Unarmored Defense doesn't apply, and Unarmored Defense is always going to be better than 9 + Proficiency unless you're intentionally trying to build someone who's useless at being a Monk. Like, maybe if you wanted to make a Strength-based Monk who dumps Dexterity and only has a Wisdom of 13... but why would you do that?

Honestly, though, if your goal is to help out characters who dumped Dexterity, why not cut out the middleman and let people calculate their AC using Strength? Maybe exclude Heavy weapons (because let's be honest here, parrying with a Greataxe is kinda difficult)? I dunno.

I will frown on giving casters automatic AC scaling, though. Seriously, Mage Armor only takes an Action to "don", and the casters that don't use Mage Armor or Shield have access to weapons anyway.

[Garfunion]

The Monk rules-tweak is almost entirely pointless - they don't get Martial Arts in any situation where their Unarmored Defense doesn't apply, and Unarmored Defense is always going to be better than 9 + Proficiency unless you're intentionally trying to build someone who's useless at being a Monk. Like, maybe if you wanted to make a Strength-based Monk who dumps Dexterity and only has a Wisdom of 13... but why would you do that?

In general to make dexterity less important.
As for the monk, it would be easier to make a strength base pugilist.

[JNAProductions]

The main point is not to replace standard armor measures. It's to make you not helpless, entirely, when caught with your pants down, and in general to represent skilled defenses of an elite adventurer.

The Monk tweak is, for 99% of builds, pointless. It's more than for completeness than anything else.