Multiple Situations of Concentration: Do They Stack?

[Odraude]

This came up in a game the other day. A wizard found himself in the threatened range of a kraken and was on the rough, open seas. Both are situations where you would need concentration (Cast Defensively and Violent Motion respectively). Does that wizard have to make two concentration checks or does he only take the worse of the two? Thank you for any help.

[Jeraa]

He has to make both checks.

[Reecy]

Yes and then if he takes damage there is another check!

[blue_the_wolf]

what if its two similar things at the same time.

for example...

I am standing next to an invisible rogue and an archer across the room has a readied action to shoot me when I cast. I begin casting magic missile. the rouge stabs me for 6 and the archer shoots me for 8 do i take 2 concentration checks (10+6+1) then (10+8+1) or do I stack them into one concentration check (10+6+8+1) or even 10+10+8+6+1+1 which would be insane...

what about continuous damage...

I am burning from the effects of a spell that has me on fire and has done 6 damage to me this round, as i start to cast magic missile the archer across the room with a readied action shoots me for 8 damage.

do I make two checks: continuous burning (10+3+1=)14 then (10+8+1=)19 for the arrow... or do I simply add the two damages for 10+3+8+1=DC22 total

last example.

it is windy with rain (5) and I am burning from acid and have taken 6 damage this turn (3) when i make the concentration check is it (10+5+3+spell level) or do I drop the wind and rain entirely?

... and if its 10+5+3+spell... does that mean the 10+10+8+6+1+1 example above is not so insane?

[Slithy]

blue_the_wolf wrote:

what if its two similar things at the same time...

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for example...
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or even 10+10+8+6+1+1 which would be insane...
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what about continuous damage...
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... does that mean the 10+10+8+6+1+1 example above is not so insane?

The short answer is that you add up the total damage but you only include the 10 and spell level once. So it is 10 + damage + spell level. So for the example of the archer and rogue above, that's 10 + 6 + 8 + 1.

For continuous damage, you count half of the most recent damage for the concentration DC.

Here is the relevant text from the PRD:

Pathfinder PRD wrote:

Injury: If you take damage while trying to cast a spell, you must make a concentration check with a DC equal to 10 + the damage taken + the level of the spell you're casting. If you fail the check, you lose the spell without effect. The interrupting event strikes during spellcasting if it comes between the time you started and the time you complete a spell (for a spell with a casting time of 1 full round or more) or if it comes in response to your casting the spell (such as an attack of opportunity provoked by the spell or a contingent attack, such as a readied action).

If you are taking continuous damage, such as from an acid arrow or by standing in a lake of lava, half the damage is considered to take place while you are casting a spell. You must make a concentration check with a DC equal to 10 + 1/2 the damage that the continuous source last dealt + the level of the spell you're casting. If the last damage dealt was the last damage that the effect could deal, then the damage is over and does not distract you.

[blue_the_wolf]

fair enough. but what about environmental.
I assume these stack....

its windy and raining 5
I am burning from acid 6 this round
I get shot with an arrow for 8 while casting.

your saying in this case it would be

10+5+3+8+spell level

or is it

5+10+3+10+8+spell level

I assume the first but just making sure.

[Eridan]

Take a look at the table :Concentration Check DCs

There you find all situations that need a concentration check. Injury while casting is one situation and wind/rain is another. The caster has to do a check for every situation.

So in your example you have to do two checks:
For rain/wind: DC5 + spell level
For injury: 10+6/2+8+spell level

Thats how i rule it. Injury and continous damage are the "same" situation on my table. I think that is RAI.

[blue_the_wolf]

OK... fair enough...

but isn't a DC5 +spell level pretty much an auto succeed? why bother with the check.

after pondering it I think those other checks are supposed to stack.

I imagine the concentration check to be a check made at the END of casting the spell in order to figure out if I did everything correctly.

If I am riding a galloping horse I am concentrating on casting during the gallop and would be making a 15+spell level concentration check at the end of the casting action but then an arrow from a readied action hits my leg adding 10+damage to the total concentration check (15+10+damage+spell).

as for damage I think it would also stack as each additional source of damage would be 10 + damage (or half damage) so if I am burning from acid which did 6 damage to me and try to concentrate through the pain to cast the spell that's (10+3+spell level) but then that darned archer catches me with another arrow this NEW pain adds an additional 10+damage to the spell resulting in a total (10+3+10+damage+spell level)

After juggling the concepts I THINK that's the intent.