Thoughts on Proficiency and AC

[Li Shenron]

It would have probably been more elegant than the current rule, since armor is the only kind of proficiency in 5e that doesn't actually grant the proficiency bonus.

I don't think the balance of the game would be broken, but numbers would be adjusted in other places. For example, there are characters who are normally not proficient in any armor, what happens to them? With this sytem, they would lag behind more and more as they level up. So one option would be to grant the proficiency bonus to everyone's AC when not wearing any armor; another option would be to grant it specific features like the Mage Armor spell or the Draconic Sorcerer's natural armor, but that's a lot more work.

And then maybe all the monster's ACs might need some revision, unless it's ok to generally boost the PCs at higher levels.

 

[UngeheuerLich]

Acceptable. Bit then magic armor never provides AC bonuses.

On the orher hand, somehow it is nice to know what AC to expect when you see what someone wears. HP is the real defensive increase.

If you like magic armor and your system, I'd do two more changes:

Unproficient saving throws now are proficient bonus -2
Proficient saving throws are now double proficiency -2
Hit points now inceease only by half max value rounded down (that is -19hp at level 20)

 

[CubicsRube]

I suggested replacing dex with the proficiency modifier some time earlier on these forums and got shut down pretty hard. It was as if i had just kicked a puppy.

People get very sensitive about ac.

I'd be interested in hearing how it plays in real life

If you look at boxers and fencers, training is as much as being able to defend yourself than simply pure agility. There are things you can train such as reflexes, knowing what to look for and how to read attacks coming to you, knowing ranges, learning different ways to step out of a strike.

So i believe there's a lot of valid logical reasons to include the proficiency modifier. As said however, it does change the assumptions thst HP rest on.

You are only talking of a change from +2 to +6 over 20 levels, most many people will never see played, so it's not game breaking.

I'd probably lower HP to compensate however.

 

[jmucchiello]

My biggest issue with this is that it waters down the effect of higher AC from armour at higher levels. I already see too many dex based characters and this would just compound that problem. Effectively you adding +1 to every characters AC every 4 levels.

Yes, but I'm not saying this should be done in a vacuum. I'm saying the system SHOULD work this way. And thus the design of monsters and other character abilities would need to be modified to make up for the change.

It's all about consistency. (And I'm still waiting for someone to say "Consistency is the hobgoblin of little minds." )

 

[TheSword]

Ha, yes I see your point. Why is AC largely static unlike other mechanics.

I suspect it’s a tradition thing. I actually like the 5e armour system with its large static bonus and strict limiting of Dex. I just gave splint mail in a treasure horde at second level and it felt worthwhile.

 

[jmucchiello]

The other benefit, perhaps, of using proficiency with AC is it means you don't need to magic armor. Although one could argue the bonuses granted by proficiency are too big: as everyone ends up with +4 armor essentially.

But again, the rest of the system would need massaging.

 

[BookBarbarian]

One of my favorite things about 5e is that low CR enemies can still hit high level PCs because AC stays relatively flat over time.

If AC scales by level I don't have that.

 

[jmucchiello]

One of my favorite things about 5e is that low CR enemies can still hit high level PCs because AC stays relatively flat over time.

If AC scales by level I don't have that.

That is a valid design concern. And it might be why proficiency doesn't apply to AC. For all we know, there was a time when proficiency did add to AC and then they removed it.

 

[Quartz]

So what happens if you use proficiency bonus with armor

This is a good way of implementing the Barbarian and Monk unarmoured AC features for Fighters when you want a cinematic campaign. They get an AC of 10 + Dex bonus (or Str bonus) + Prof bonus + shield. I might even allow it for light armour types.

 

[pming]

Hiya!

Interesting idea. The problem I see, however, is that it seems to "double dip" the durability/skill of higher and higher level PC's. If you were doing a low-magic, gritty game where PC's never gained more HP past 3rd level (or 5th, or whatever), then it would probably be a nice addition. The thing is that, as 5e is now, "AC" goes hand in hand with "Hit Points" in terms of PC/Creature durability.

That's why "higher CR" critters tend to have more HP's, but keep the AC on the bounded accuracy scale. What AC *and* HP do is basically equate to "this is how hard it is to kill this guy". If you have AC 16 at 3rd level, and you have AC 16 at 13th level...it's the HP's that help to define how "much" or how "hard" you got hit as much as AC. Increasing both AC and HP based on level is...as I said, sort of "double dipping" into the survivability pool.

^_^

Paul L. Ming