Playing around with the CR calculator

Post/Author/DateTimePost
#1

Xeviat-DM

May 14, 2015 22:25:26

So, I ran a Great Weapon Fighting Battlemaster Fighter through the CR calculator, curious about what I'd get. This is more for playing around with things and evaluating NPCs than it is for balancing the classes, but I thought it would offer some interesting insights. First, it is very clear that the monster/npc design is entirely separate from the player design. I have a few other observations from all this, but they're incredibly biased and really only support my hypothesis going in, so that's not really the point of this.

 

Also, as I was evaluating a PC, I made a few assumptions. "Standard Day" in the DMG is about 6 encounters with 2 short rests, so short rest abilities were divided by 2 and daily (of which there were none) were divided by 6 to determine their bonus. The fighter's offensive ability would spike a bit if I let them use all of their short rest abilities in one fight (actually, it increases its CR by 2 at 20th level).

 

Lvl 1
Defensive CR 1/4, Offensive CR 2, Average CR 1
Lvl 2
Defensive CR 1/4, Offensive CR 2, Average CR 1
Lvl 3
Defensive CR 1/4, Offensive CR 3, Average CR 2
Lvl 4
Defensive CR 1, Offensive CR 3, Average CR 2
Lvl 5
Defensive CR 1, Offensive CR 5, Average CR 3
Lvl 6
Defensive CR 2, Offensive CR 5, Average CR 4
Lvl 7
Defensive CR 3, Offensive CR 5, Average CR 4
Lvl 8
Defensive CR 3, Offensive CR 6, Average CR 5
Lvl 9
Defensive CR 4, Offensive CR 6, Average CR 5
Lvl 10
Defensive CR 5, Offensive CR 6, Average CR 6
Lvl 11
Defensive CR 5, Offensive CR 9, Average CR 7
Lvl 12
Defensive CR 6, Offensive CR 9, Average CR 8
Lvl 13
Defensive CR 6, Offensive CR 9, Average CR 8
Lvl 14
Defensive CR 8, Offensive CR 9, Average CR 9
Lvl 15
Defensive CR 9, Offensive CR 9, Average CR 9
Lvl 16
Defensive CR 9, Offensive CR 9, Average CR 9
Lvl 17
Defensive CR 10, Offensive CR 11, Average CR 11
Lvl 18
Defensive CR 10, Offensive CR 12, Average CR 11
Lvl 19
Defensive CR 11, Offensive CR 12, Average CR 12
Lvl 20
Defensive CR 12, Offensive CR 13, Average CR 13

 

At first, this fighter's offense outstrips its defense by a wide margin; as it should, it's a great weapon fighter. That pulls back a bit at higher levels, evening out briefly from level 15 and 16 (after I boosted Con actually).

 

As the fighter is one of the more defensive classes, this offense/defense shift will likely increase with other classes. This is probably why the monster HP is so high.

 

So, this level 20 fighter, CR 13, is worth 10,000 xp. A party of 4 of these fighters vs. 4 of these fighters is somewhere between a hard and a deadly fight (hard is 8,500, deadly is 12,700). I like that. I'm glad to see the CR calculator didn't create some weird result when looking at the encounter guidelines. (CR 15, which would be what the fighter would be if they used up all their short rest resources in one fight, is 13,000 xp, which is greater than a deadly fight; when you have basically a 50/50 shot, it better be called deadly).

#2

LordCorwin

May 15, 2015 7:35:57

This seems right on. After all, look at the NPC Archmage in the back of the Monster Manual. He's an 18th level spellcaster with a CR of 12.

#3

Sword_of_Spirit

May 15, 2015 12:32:19

You made a mistake by assuming that sustained damage output matters for CR.

 

As per the DMG, you need to only take into account only how much damage they can put out in the first three rounds of combat, and then average those numbers together to get the average damage output per round over those first three rounds. So for your fighter you need to assume he uses Action Surge on round 1, and if he's high level, uses it again on round 2. Assume he goes nova and blows everything he can towards increasing his damage output in those first three rounds. That means all of his superiority dice go into the most damage causing maneuvers. For defence, you need to determine the total amount of effective hit points he can have at his disposal. Increase his hit points by the hp he would gain by using Second Wind.

 

If he has the Parry maneuver, then run all the calculations again assuming he uses his reaction to use parry each of those three rounds, and adding the results to his hit points (don't average it per round, just increase his hit points for each time your use it). If the increase in his defensive value by diverting 3 dice into Parry raises his overall CR more than using those three dice for damage, then use the overall CR you get from this value. (If you really want to get into minute details, you can divert less than 3 superiority dice to find the ideal assignment of dice, but that's probably unneccessary.)

 

If it were a wizard with mage armor, you would treat his AC as if he had it cast already. If he also knows shield, you assume he uses his reaction to cast it each round (unless that cuts into damage output by taking important spell slots) and treat his AC as the higher value that would give him.

 

In other words, you don't let them use all of their short rest abilities as an alternate CR determination, you require them to use all of their best short (and long) rest abilities to determine their proper CR.

 

It still isn't going to give him a CR 20 at level 20, but the numbers will get closer.

#4

Xeviat-DM

May 15, 2015 14:45:33

Yes, I assumed the fighter went nova, just like the CR calculator assumes that a dragon drops its breath weapon early. I did choose to only use offensive superiority dice uses because they're supposed to be equal; using them for defense would boost defense and reduce offense. And, as I said in my first post, I showed how letting the fighter use all of their short rest abilities in one fight would skew the CR; it increases it by 2 at 20th level. Mostly, I was running the numbers to get an idea of what the player performance compared to monsters. (I did take into account second wind; it's not a huge gain).

 

Again, this was mostly to see what things would look like (I initially did it to compare druid of the moon wildshaping to a fighter in another thread).

#5

FFSAA

May 15, 2015 23:04:16

Level 20 human FTR-ek.  20 str, 20 con, 13 chr.  311 HP (second wind, leadership).  AC 24 (shield spell).

Great Weapon Master

Leadership

Polearm Master

Tough

 

(20d10 + 2d4 + 220 + 110) / 3 rounds is around 160 damage/round.  8 attacks + 1 bonus followed by 8 attacks + 1 bonus followed by 4 attacks + second wind.

 

Defensive challenge rating is 19.  Offensive challenge rating is 20.  Effective CR is 20.

 

This doesn't even take into consideration potentially haveing Magic Weapon spell active for a +2 weapon for additional damage.  Animate Dead spell for additional support.  Stoneskin, Blur etc.  Nor irelentless endurance if horc, indomitable or the fighter's teleport ability.

 

This is 5 higher than the CR you came up with.  He could be even higher I think if he was a ranged fighter, slightly lower damage but more AC, higher attack bonus.  Certainly more deadly as it would combo well with his teleport.

#6

Mal-Duroth

May 16, 2015 13:09:15

Where is this CR calculator?

#7

Xeviat-DM

May 16, 2015 20:56:36

DMG

(Reply to #5)

Xeviat-DM

FFSAA wrote:
(Reply to #7)

Mal-Duroth

Xeviat-DM wrote: