D&D 5E DMG page 274.

[Psikerlord#]

is there something about adding caster levels to monsters? Eg, say I want to add 10 levels of spellcaster to a dragon. Easy to do and work out the new CR?

 

[Leatherhead]

is there something about adding caster levels to monsters? Eg, say I want to add 10 levels of spellcaster to a dragon. Easy to do and work out the new CR?

On page 283 they cover it a bit loosely. Basically if the class levels grant them note damage than normal, you bump them up appropriately. Likewise for defensive spells or powers. In the example, 5 wizard levels do not up the CR of the Ancient Red, mostly because the bonuses are a drop in the bucket at that point.

 

[Psikerlord#]

On page 283 they cover it a bit loosely. Basically if the class levels grant them note damage than normal, you bump them up appropriately. Likewise for defensive spells or powers. In the example, 5 wizard levels do not up the CR of the Ancient Red, mostly because the bonuses are a drop in the bucket at that point.

ah ok it is a bit fast and loose i guess, that's cool

 

[Chocolategravy]

This is the #1 reason I'm even buying a DMG, so I'm glad to hear you think they did it right!

Sounds like putting it in the DMG rather than the MM worked.

 

[TarionzCousin]

The original post and title of this thread reminded me of this joke:

[sblock]A new inmate arrived in prison.

At nighttime lights out, someone shouted out "16," and everyone laughed. Someone else said "23," and people cracked up again. Someone else said "45," and everyone was rolling in laughter.

The new guy asked his cellmate what was going on and was told that the prisoners had all been together so long that they knew all the jokes. So instead of reciting the whole joke they had numbered them and just said the numbers.

The new guy wanted to fit in, so he yelled out "29," and nothing happened. There was no response. Again, he shouted "29," and got no reaction. So the new guy asked his cellmate what was wrong and was told "Some people just can't tell a joke."
[/sblock]

 

[Joe Liker]

Sounds like putting it in the DMG rather than the MM worked.

Not really -- I would have bought it for reasons 2 through 10, regardless.

 

[JEB]

Only issue with the table is that it gives you a range of hit points per CR, and an amount of damage per round per CR, but doesn't seem to be very helpful about reverse-engineering those into dice. (I'm working on a spreadsheet to sort that out, though I wonder if I'll be allowed to share it...)

Otherwise, that whole section is vastly more detailed than I expected, pretty great!

 

[Leatherhead]

Only issue with the table is that it gives you a range of hit points per CR, and an amount of damage per round per CR, but doesn't seem to be very helpful about reverse-engineering those into dice. (I'm working on a spreadsheet to sort that out, though I wonder if I'll be allowed to share it...)

Otherwise, that whole section is vastly more detailed than I expected, pretty great!

Hit Dice are easy: They are based on creature size. The trick is "effective hit points" which are modified by features (like regeneration or undead fortitude), resistances, and immunities. And even then it's mostly just a multiplier.

The DPR, on the other hand, is a beast to figure out. It is meant to be the average damage of the monster "going nova" with the best attack routine, and aura, and whatever other source of damage (like a breath weapon) landing for the first three rounds. AoE effects have a massive impact on this as they add up damage done to all targets. It also ignores sub-optimal attacks (like throwing a rock instead of swinging a sword twice).

I can see why you would want a spreadsheet for such things.

 

[JEB]

Hit Dice are easy: They are based on creature size.

Size and the monster's Constitution bonus. As a result, not so easy as you'd think, unless you have the patience to keep trying HD/Con bonus combinations until you get one within the range...

The DPR, on the other hand, is a beast to figure out. It is meant to be the average damage of the monster "going nova" with the best attack routine, and aura, and whatever other source of damage (like a breath weapon) landing for the first three rounds. AoE effects have a massive impact on this as they add up damage done to all targets. It also ignores sub-optimal attacks (like throwing a rock instead of swinging a sword twice).

I can see why you would want a spreadsheet for such things.

Yep...

 

[aramis erak]

Size and the monster's Constitution bonus. As a result, not so easy as you'd think, unless you have the patience to keep trying HD/Con bonus combinations until you get one within the range...

No, you don't.
Divide the target HP by (average per die + Con Modifier)...

Simple algebraic solving for Y.

So, let's say you want 221-235 (CR11), and you have a medium critter (thus d8's), and Con 22 (for +6)...

Hd = Thp / (Apd + Conmod)
Hd = 235 / (4.5 + 6)
Hd = 235/10.5 = 22.38.
So, we give it 22 HD, and 22x10.5 = 220+11=231hp
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