Concentration

[sparxmith]

Last gaming session, the groups rules lawyer brought up an argument about concentration. We play 3.5, and had been playing by the rule that if you are damaged in the turn that you cast a spell you had to make a concentration check 10 + spell level + damage dealt to be able to cast the spell.

An example

Rogue Bill attacks first, initiative count 20. He moves forward and attacks Wizard Tim with a rapier. He hits, and because Wizard Tim is flat-footed, adds sneak attack damage. 1d6 + 1 + 1d6 = appx 8 pts of damage.

Wizard Tim, acting next on count 17, wants to cast a spell, magic missile, at Rogue Bill. To do so, he must first succeed on a concentration check of 19.


Now, I'm not the DM of this game, I just happen to be the only member of the group who like to post on message boards--so I got stuck with the question. I just re-read the rule on concentration both in 3.0 and 3.5, and I no longer believe that our rule is correct. I believe the rules lawyer is correct. His argument is that you must succeed on a concentration check when someone interupts your spell casting--with an AoO, readied action, etc.

Looking at the above example, I figure that if Wizard Tim is first level, and has a constitution of 12, he has about a 30% chance of succeeding on this check, which really doesn't seem right. (He succeeds on a die role of 14, not very good odds.)

What's the correct ruling? I'll report it back to the DM for next session.

Thanx,

Sparxmith

 

[James McMurray]

you must succeed on a concentration check when someone interupts your spell casting--with an AoO, readied action, etc.

This is correct.

 

[Scion]

Yep, the rule you were going by before is more of a second edition bastardization to third. A lot of groups have this problem though

It doesnt matter if you are hit by something at another time, only if you are taking damage during the casting of the spell (or in response to you starting it, aoo's and readied actions are funny about timing).

As james said of course He is right at least 50% of the time.

Edit:
SRD:
10 + damage dealt || Damaged during the action.2

2 Such as during the casting of a spell with a casting time of 1 round or more, or the execution of an activity that takes more than a single full-round action (such as Disable Device). Also, damage stemming from an attack of opportunity or readied attack made in response to the spell being cast (for spells with a casting time of 1 action) or the action being taken (for activities requiring no more than a full-round action).

 

[James McMurray]

In all modesty I think it is probably closer to 53%, thank you very much!

 

[Scion]

Hey, I said at least, had to give you the benefit of the doubt james