D&D 5E Drawbacks to Increasing Monster AC Across the Board?

[Uni-the-Unicorn!]

LOL I don't know how many PCs you have in your group, but in my games at level 15 CR appropriate solos are like CR 19-20. At 24-26 you'd be dead, dead, dead.

We have 5-6 depending on who shows up. At those numbers right around level +10 is appropriate for a real challenge (risking TPK). Anything less than that is basically a guaranted win IME

I just checked the new DMG guidelines and is what we do falls in line with the 2024 hard encounter. So I guess we are doing it right!

 

[UngeheuerLich]

I like lower to hit and fewer HP as it makes combat faster and feel more dangerous due to less time spend updating HPs and more risk from a “lucky” streak.

Unfortunately I wouldn’t want to mess with it in an existing system like 5E as it affects other things. Damage spells that bypass AC become more potent, for example.

In my recent games I noticed, that giving CR < 1/2 mobs better armor and some extra str or dex really makes them really nice minions. AC 18 (chain + shield) and +5 to hit, 1d8+3 damage with around 11 to 14 hp is usually enough to make them a threat. 11 hp means a level 1 burning hands kills them on a failed save with a 50% chance. 14 hp is a round a 50% chance to kill them with a second level spell slot. A fireball deals 8d6 damage. This is an average damage of (8+48)/2 = 28. So even a kill on a successful save with 50% chance.
Note that this is the same double damage increase as extra attack classes have.
Note that a rogue deals 3d6+3 or 4 damage at level 3 or 4, which also averages 14 hp.
A great sword battle master deals 2d6+3 + 1d8 damage. Again an average of 14.5.

So long story short: if you use high AC mobs, try to aim for 11 to 14 hp. This makes them go down in one ore two hits or one or two spell hits. So high AC does not end in a slogfest.

Although I technically hate the hobgoblin statblock for several reasons, hobgoblins are the poster child for that design. They are perfect high level minions. Only +3 to hit but usually with advantage. High damage. But easy to kill with spells. Be careful when using them at low levels. Their ranged attack is way too much against low level characters. Against high level characters this might balance out because half of them might be dead before they actually take their turn.

 

[ezo]

I just checked the new DMG guidelines and is what we do falls in line with the 2024 hard encounter. So I guess we are doing it right!

LOL there's no right or wrong about it. And this is tagged for 5E, not 2024, so why are you looking there?

Anyway, if level 15 PCs have to face CR 25 creatures for a "hard encounter" in 2024, I am even more glad I am steering away from it.

 

[Tonguez]

This is the direction I am leaning, personally. I really liked some of the concepts in Nimble 5E, for example, but now it has moved on to full-blown Nimble 2 I am not as much of a fan.

I prefer keeping the attack roll and abandoning damage (just go to hits) simply because it keeps the focus on building PC skill and not on getting bigger weapons - weapons shouldnt matter, a skilled fighter can kill you just as easily with a knife as with giant battle axe

 

[Stalker0]

Since there is a lot of discussion about what the hit rate translates to in game I thought this quick chart would be helpful. If you assume a 65% hitrate, two attacks (aka most fighter types). And then we assume a damage of 12.5 (1d8 + 5 str +2 for something like dueling mastery + 1 magic bonus). And then here is the average damage that character will do, the % of the time they do it, both for regular, advantage, and disadvantage. So you can guage for yourself how wide a variance in damage the character will do.

 

[ezo]

I prefer keeping the attack roll and abandoning damage (just go to hits) simply because it keeps the focus on building PC skill and not on getting bigger weapons - weapons shouldnt matter,

FWIW a while ago our DM did average damage for creatures and allowed us players do use average damage if we wanted instead of rolling.

Hitting is too easy in 5E, and if you use magic items, spells, flanking (at all), etc. it is even easier. There's really nothing to "build".

Not to say you couldn't create a system to do this, but 5E as is doesn't.

a skilled fighter can kill you just as easily with a knife as with giant battle axe

I disagree wholeheartedly with this statement (assuming adequate space, etc. to properly wield either weapon that is...).

Weapons absolutely matter in a real fight and so should also in a fantasy game IMO.

 

[tetrasodium]

Since there is a lot of discussion about what the hit rate translates to in game I thought this quick chart would be helpful. If you assume a 65% hitrate, two attacks (aka most fighter types). And then we assume a damage of 12.5 (1d8 + 5 str +2 for something like dueling mastery + 1 magic bonus). And then here is the average damage that character will do, the % of the time they do it, both for regular, advantage, and disadvantage. So you can guage for yourself how wide a variance in damage the character will do.

View attachment 405363

It looks like you are trying to map some of the percentages noted in post76. It's good that you don't appear to have made the common statistical mistake of multiplying the average damage across a statistically significant number of attacks (IoW hundreds)

Spoiler: why I say it is *usually* a mistake

That "average" is only part of the story and not quite accurate though. You need many many attacks before you can have enough to get an "average" for a lot of those. Outside of scenarios like the thought experiment white room sarakokra vrs tarrasque&other endless solo fight battles there are almost no monsters with enough hp to establish those averages because there is typically other party members and the monsters die when they hit zero rather than sticking around to accrue enough statistical data for some kind of WoW raid stats application type output.

With that said, post 76 was not suggesting that switch, it was noting a potential instance of Garbage in Garbage out math assumptions that could have made the 65% hit rate before magic items and buffs seem reasonable.

Diving deeper into the attack by attack 65%>42%>27%>17% chain that ends on the first miss in that post65... It would be much more difficult to calculate because there were a lot of monsters intended to have some rock paper scissors style ac/save/hp/dpr slider roles in 3
X, but given the expectation of PCs regularly accumulating both +attrib and +mod weapons on top of (de) buffs I wouldn't be surprised if a 4 attack chain with the old full/-5/-10/-15 iterative attack penalty came in with an average that was close enough to that 65/42/27/17 to make a comparison for discussion.

Monster design was radically different between 3.x &5e when it comes to hp & it very much matters there. In 5e the monster how is massively inflated because almost every attack is pretty much assumed to hit... in 3.x though it depends somewhat if the monster's ac was tuned to full or fractional BaB progression but was only the earlier parts of the chain expected to hit with the later being gravy that sped up the fight

 

[Uni-the-Unicorn!]

LOL there's no right or wrong about it. And this is tagged for 5E, not 2024, so why are you looking there?

Anyway, if level 15 PCs have to face CR 25 creatures for a "hard encounter" in 2024, I am even more glad I am steering away from it.

We are playing 2014 I just had a had to the 2024 books handy.

Haven’t you heard about people throwing 3x deadly encounters are their players in 2014?! What we do is not that extreme, so I don’t think we are out of the norm.

FYI, The encounter math is basically the same but simplified in 2024 and pretty much everyone agrees it is better. They just dropped the easiest and renamed them (mostly). The biggest improvement was getting rid of the multiple monster mulitploer