D&D 5E Mined results: Average AC by play tier

[Puutuulion]

I see a lot of debate about mechanical effectiveness of combat feats (example: GWM and Sharpshooter) and so wanted to provide some mined data on AC. Below is Average AC by play tier. Most creature types fall into the "Most Types" bucket, but two are typically higher AC (constructs + dragons) and two are typically lower (Giants & Oozes.)

The average is weighted by creature type (shown number is an average of averages by creature type.)

CR <1 is excluded because AC is highly variable below CR 1, and generally horde-type threats are irrelevant to the 'vs AC' discussions. I have also excluded the Tarrasque, which has the highest CR/AC of 30/25, respectively.

This data comes from 409 stat blocks found in the monster manual & DM basic rules.

[TABLE="class: grid, width: 500, align: center"]
[TR]
[TD]CR[/TD]
[TD]Most Types[/TD]
[TD]Constructs[/TD]
[TD]Dragons[/TD]
[TD]Giants[/TD]
[TD]Oozes[/TD]
[/TR]
[TR]
[TD]1-4[/TD]
[TD]13.3[/TD]
[TD]15.5[/TD]
[TD]16.4[/TD]
[TD]11.7[/TD]
[TD]7.0[/TD]
[/TR]
[TR]
[TD]5-8[/TD]
[TD]15.4[/TD]
[TD]13.0[/TD]
[TD]16.9[/TD]
[TD]14.9[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]9-12[/TD]
[TD]17.1[/TD]
[TD]15.5[/TD]
[TD]18.0[/TD]
[TD]16.0[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]13-16[/TD]
[TD]17.8[/TD]
[TD]20.0[/TD]
[TD]18.5[/TD]
[TD]16.0[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]17-20[/TD]
[TD]19.0[/TD]
[TD][/TD]
[TD]19.5[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]21-24[/TD]
[TD]19.5[/TD]
[TD][/TD]
[TD]21.8[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[/TABLE]

 

[Plaguescarred]

See how a Strenght 12 frontline PC can still pull his own and get even better at it as he gain levels, magic items, buffing etc....

 

[Plaguescarred]

It's surprising how monsters AC stays relatively low in average!

PS Thanks @Puutuulion for mining all this data

 

[cheezitmojo]

Interesting that it's a larger leap from 1-8 (2 ASIs for single class characters) than it is from 9-20 (3 ASIs). I wonder if that's because the developers assume that attack stats will be maxed ASAP and then players will focus on something else for higher-level play.

 

[mellored]

Add a column to compensate for +proficency.

[TABLE="class: grid, width: 600, align: center"]
[TR]
[TD]CR[/TD]
[TD]Most Types[/TD]
[TD]Roll needed to
hit with 16 Str
[/TD]
[TD]Constructs[/TD]
[TD]Dragons[/TD]
[TD]Giants[/TD]
[TD]Oozes[/TD]
[/TR]
[TR]
[TD]1-4[/TD]
[TD]13.3[/TD]
[TD]8.3[/TD]
[TD]15.5[/TD]
[TD]16.4[/TD]
[TD]11.7[/TD]
[TD]7.0[/TD]
[/TR]
[TR]
[TD]5-8[/TD]
[TD]15.4[/TD]
[TD]9.4[/TD]
[TD]13.0[/TD]
[TD]16.9[/TD]
[TD]14.9[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]9-12[/TD]
[TD]17.1[/TD]
[TD]10.1[/TD]
[TD]15.5[/TD]
[TD]18.0[/TD]
[TD]16.0[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]13-16[/TD]
[TD]17.8[/TD]
[TD]9.8[/TD]
[TD]20.0[/TD]
[TD]18.5[/TD]
[TD]16.0[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]17-20[/TD]
[TD]19.0[/TD]
[TD]9[/TD]
[TD][/TD]
[TD]19.5[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]21-24[/TD]
[TD]19.5[/TD]
[TD]-[/TD]
[TD][/TD]
[TD]21.8[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[/TABLE]

Ignoring 1-4, since those are quick levels and many of those creatures would die in 1 hit without GWM...

The average roll needed to-hit is 9.575. Or 52.125% accuracy.

 

[mellored]

Interesting that it's a larger leap from 1-8 (2 ASIs for single class characters) than it is from 9-20 (3 ASIs). I wonder if that's because the developers assume that attack stats will be maxed ASAP and then players will focus on something else for higher-level play.

No, I just think they just pushed the 1-4 creatures down a notch.
Ignore that and it's +/- a single point.


+2 Str really does put you ahead of the curve.

 

[cheezitmojo]

Add a column to compensate for +proficency.

Ignoring 1-4, since those are quick levels and many of those creatures would die in 1 hit without GWM...

The average roll needed to-hit is 9.575. Or 52.125% accuracy.

That added column really helps. It looks like ACs were arranged so the "money levels" (Tiers 2 & 3) rely more on the dice being hot than the modifiers, unless I'm reading it wrong.

 

[cooperjer]

This is great info. How does it compare to the table in the DMG for creature design? I'm AFB right now, but based on memory it appears to be fairly close.

The other aspect to how effective combat feats are, is related to the HP of the creature. Is ten points of damage to a creature 1/4, 1/8, or 1/24th of it's health? I suspect the table in the DMG on creature design provides a fairly good estimate of the HP by CR as well.

 

[Puutuulion]

This is great info. How does it compare to the table in the DMG for creature design? I'm AFB right now, but based on memory it appears to be fairly close.

The other aspect to how effective combat feats are, is related to the HP of the creature. Is ten points of damage to a creature 1/4, 1/8, or 1/24th of it's health? I suspect the table in the DMG on creature design provides a fairly good estimate of the HP by CR as well.

Average HP:

[TABLE="class: grid, width: 500, align: center"]
[TR]
[TD]CR[/TD]
[TD]Most Types[/TD]
[TD]Constructs[/TD]
[TD]Dragons[/TD]
[TD]Giants[/TD]
[TD]Oozes[/TD]
[/TR]
[TR]
[TD]1-4[/TD]
[TD]49[/TD]
[TD]36[/TD]
[TD]36[/TD]
[TD]58[/TD]
[TD]71[/TD]
[/TR]
[TR]
[TD]5-8[/TD]
[TD]100[/TD]
[TD]118[/TD]
[TD]125[/TD]
[TD]124[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]9-12[/TD]
[TD]159[/TD]
[TD]156[/TD]
[TD]169[/TD]
[TD]181[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]13-16[/TD]
[TD]170[/TD]
[TD]210[/TD]
[TD]201[/TD]
[TD]230[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]17-20[/TD]
[TD]222[/TD]
[TD][/TD]
[TD]282[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]21-24[/TD]
[TD]291[/TD]
[TD][/TD]
[TD]451[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[/TABLE]

 

[Xeviat]

This is great info. How does it compare to the table in the DMG for creature design? I'm AFB right now, but based on memory it appears to be fairly close.

This data comes from 409 stat blocks found in the monster manual & DM basic rules.

[TABLE="class: grid, width: 500, align: center"]
[TR]
[TD]CR[/TD]
[TD]Most Types[/TD]
[TD]Constructs[/TD]
[TD]Dragons[/TD]
[TD]Giants[/TD]
[TD]Oozes[/TD]
[/TR]
[TR]
[TD]1-4[/TD]
[TD]13.3[/TD]
[TD]15.5[/TD]
[TD]16.4[/TD]
[TD]11.7[/TD]
[TD]7.0[/TD]
[/TR]
[TR]
[TD]5-8[/TD]
[TD]15.4[/TD]
[TD]13.0[/TD]
[TD]16.9[/TD]
[TD]14.9[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]9-12[/TD]
[TD]17.1[/TD]
[TD]15.5[/TD]
[TD]18.0[/TD]
[TD]16.0[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]13-16[/TD]
[TD]17.8[/TD]
[TD]20.0[/TD]
[TD]18.5[/TD]
[TD]16.0[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]17-20[/TD]
[TD]19.0[/TD]
[TD][/TD]
[TD]19.5[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[TR]
[TD]21-24[/TD]
[TD]19.5[/TD]
[TD][/TD]
[TD]21.8[/TD]
[TD][/TD]
[TD][/TD]
[/TR]
[/TABLE]

[TABLE="width: 500"]
[TR]
[TD]CR[/TD]
[TD]AC[/TD]
[/TR]
[TR]
[TD]1-4[/TD]
[TD]13-14[/TD]
[/TR]
[TR]
[TD]5-8[/TD]
[TD]15-16[/TD]
[/TR]
[TR]
[TD]9-12[/TD]
[TD]16-17[/TD]
[/TR]
[TR]
[TD]13-16[/TD]
[TD]18[/TD]
[/TR]
[TR]
[TD]17-20[/TD]
[TD]19[/TD]
[/TR]
[TR]
[TD]21-24[/TD]
[TD]19[/TD]
[/TR]
[/TABLE]

Looks nearly exactly to me. By the DMG table, typical monster AC goes up at the following levels: 4, 5, 8, 10, 13, 17. Interestingly, proficiencies go up at 5, 9, 13, 17, and if you start with a 16 attack stat, your attack score will probably go up at levels 4 and 8. 4, 5, 8, 9, 13, 17 nearly lines up exactly with 4, 5, 8, 10, 13, 17, which is why I've been arguing constantly that player attack scales almost perfectly with standard monster AC. The analysis of the monsters match that. Magic weapons are purely gravey.

Monster Attack vs. Player AC is a different story; monster attack bonuses continue to scale.