Trap that casts Sirocco = CR56. What?


Rules Questions


I'm trying to determine the CR of a trap that casts the spell sirocco. Here are the guidelines for determining the CR of a spell that does damage:

PRD wrote:
Average Damage: If a trap (mechanical or magical) does hit point damage, calculate the average damage for a successful hit and round that value to the nearest multiple of 10. If the trap is designed to hit more than one target, multiply this value by 2. If the trap is designed to deal damage over a number of rounds, multiply this value by the number of rounds the trap will be active (or the average number of rounds, if the duration is variable). Use this value to adjust the Challenge Rating of the trap, as indicated on Table: CR Modifiers for Mechanical Traps.
PRD wrote:

Table: CR Modifiers for Magic Traps

Feature CR Modifier
Highest-level spell effect + Spell level
Damaging spell effect +1 per 10 points of average damage

So, if I'm reading this correctly, here's how I calculate the CR for my sirocco trap: A CL 11 sirocco inflicts an average of (4d6+11) = 25 damage. Because sirocco is an area affect spell that damages multiple people, I multiply this value by 2. Because a CL 11 sirocco will last for 11 rounds, I multiply my total by 11. So 25 x 2 x 11 = 550. Using the CR Modifiers for Magic Traps my trap's CR is +1 per 10 points of damage, so 550/10 = +55 CR. The base CR of a magic trap that casts a spell is 1 plus the highest spell level or the average damage formula, whichever is higher. So the final CR of my sirocco trap is CR56.

This is obviously a ridiculous result. What mistake am I making?


You have it wrong it is
avg 25 damage round to 3
multiply by 2 = 6
then 11 rounds gives CR 60
:(

Or use your own judgement and pick the CR which you think is appropriate.
Will the trap pin the players in the area of effect ? if it will not then the duration us not really important as the characters will not be in it .


Pathfinder Roleplaying Game Superscriber

They can crawl out of the effect. The multiplier only makes sense for damage that continues regardless of player actions (other than saves).


The trap CR rules frequently give nonsensical results, and the damage-dealing spell modifier is one of the biggest culprits. I'm going to be completely blunt: there is no reason for this modifier to exist, and will virtually always result in an over-CR'd trap when you apply it. There is legitimate reason to be cautious when dealing with large sums of instantaneous damage, but that's true of monsters and NPC's too and they don't have this weird rule.

If you ignore the damage rule, then the Sirocco trap comes in a CR 7. This is fairly reasonable, and if I had to make an ad-hoc judgement that's what I'd go with for a Sirocco trap. A Wizard NPC who can cast Sirocco is going to be CR 10, so a trap that can only activate sirocco and does not intelligently target the PC's is necessarily much less threatening, so CR 7 seems about right to me.


You could also play the CR game by saying that the Sirocco in the trap is from a Wood Elementalist Wizard, making it a CL 7 spell. Avg damage is reduced to 21, rounds to 7.

That brings our friendly neighborhood Sirocco down to a paltry CR 29.


Dasrak wrote:

The trap CR rules frequently give nonsensical results, and the damage-dealing spell modifier is one of the biggest culprits. I'm going to be completely blunt: there is no reason for this modifier to exist, and will virtually always result in an over-CR'd trap when you apply it. There is legitimate reason to be cautious when dealing with large sums of instantaneous damage, but that's true of monsters and NPC's too and they don't have this weird rule.

If you ignore the damage rule, then the Sirocco trap comes in a CR 7. This is fairly reasonable, and if I had to make an ad-hoc judgement that's what I'd go with for a Sirocco trap. A Wizard NPC who can cast Sirocco is going to be CR 10, so a trap that can only activate sirocco and does not intelligently target the PC's is necessarily much less threatening, so CR 7 seems about right to me.

I'm probably going to go with this. I'd like to boost the CR up to the 9-10 range, since the PCs are level 14, so I'll probably just look at some sample traps in that range and adjust accordingly.


The module "Moonscar" has a trap that is... spoilers for the rest just in case:

Moonscar Spoiler:
a Symbol of Death trap that is triggered by looking at it. It's only a CR 16 with a CL of 20.

So yeah, the DC calculations are kind of totally wrong.

Lantern Lodge Customer Service Manager

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Removed post and reply. Do not use the r-word or words meant to be a play on it. .


Are words like 'idiot' alright?
Or any other word that has mostly lost whatever meaning it used to have and is now a general insult?


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On these boards, it's generally a good idea not to use insults in your posts, no matter how 'general' and whether or not they might (or might not) have 'mostly' lost their former meaning.


1 person marked this as a favorite.

If you can't make your point without insulting those with an opposing/differing view on the rules... you should probably stop to rethink things.

Lantern Lodge Customer Service Manager

CrystalSeas wrote:
On these boards, it's generally a good idea not to use insults in your posts, no matter how 'general' and whether or not they might (or might not) have 'mostly' lost their former meaning.
Ambrosia Slaad wrote:
If you can't make your point without insulting those with an opposing/differing view on the rules... you should probably stop to rethink things.

Both of these answers are correct. Paizo.com strives to be a welcoming and friendly place, insults do not contribute to that goal.


Anyways....CR is a measure of challenge and threat. If the trap isn't likely to cause damage over more than a round or two, regardless of the actual duration of the spell, rate it accordingly.

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