Concentration Checks : I hope I'm wrong.

[Baron_Yves]

In doing some research on my magic wielding NPCs I ran across this bit in the SRD:

Spell

If you are affected by a spell while attempting to cast a spell of your own, you must make a concentration check or lose the spell you are casting. If the spell affecting you deals damage, the DC is 10 + the damage taken + the level of the spell you're casting.

If the spell interferes with you or distracts you in some other way, the DC is the spell's saving throw DC + the level of the spell you're casting. For a spell with no saving throw, it's the DC that the spell's saving throw would have if a save were allowed (10 + spell level + caster's ability score).

Is this saying that a player, while under the effects of any spell, must make a concentration check to cast another spell?

Example: Player A has Mage Armor cast on them, then in a following round tries to cast Magic Missile. Does the Magic Missile spell require a concentration check?

Thanks for any insight.

-Yves

[Are]

No. The mage armor doesn't deal damage to you, interfere with you, or distract you. Spells that do one of those three things are the only spells forcing a concentration check.

[Baron_Yves]

I see. So the first part of the section is simply stating that when affected by certain types of spells a concentration check is needed, and the subsequent sentences go on to explain those specific types.

Is it defined somewhere what counts as 'interference'?

For instance, would the effects of a Cleric's Bane spell act as interfering with someone?

-Y

[Valantrix1]

Spells such as Bane would not affect a caster. In this case "interference" usually meas something that would restrict there movement.

[Marthian]

Baron_Yves wrote:

I see. So the first part of the section is simply stating that when affected by certain types of spells a concentration check is needed, and the subsequent sentences go on to explain those specific types.

Is it defined somewhere what counts as 'interference'?

For instance, would the effects of a Cleric's Bane spell act as interfering with someone?

-Y

As far as I know, the effects will not interfere. But readying an action to cast Bane when they cast a spell may, however.

[Silent Saturn]

I would think that a spell would say outright if it interferes with spellcasting. Though since any offensive spell will likely have been cast by an enemy under the DMs control, you can just wait for him or her to tell you that the spell you're under is interfering with you.

The important thing is that your own personal spells (Mage Armor, True Strike, etc.) will never interfere with you.

[mplindustries]

Spells and effects that interfere with you and force Concentration rolls say as much in their descriptions.

[DeathQuaker]

Baron_Yves wrote:

I see. So the first part of the section is simply stating that when affected by certain types of spells a concentration check is needed, and the subsequent sentences go on to explain those specific types.

Is it defined somewhere what counts as 'interference'?

For instance, would the effects of a Cleric's Bane spell act as interfering with someone?-Y

As a guideline, I would suggest looking at what other situations force a Concentration check. If a spell creates such a situation, then it also forces a concentration check.

So, the other things which force a concentration check (besides the usual casting defensively) are...

- Taking damage
- Being grappled or pinned
- Vigorous or violent motion
- Violent weather
- Being entangled

So spells which might force you to make a concentration check...
- Any damaging spell if you are casting a spell that takes more than 1 standard action to cast and it hits you before you are finished, or any spell which deals continuous damage, such as acid arrow
- Standing in a field of black tentacles
- Falling victim to a gust of wind spell, if you are susceptible, or perhaps even spells which may bull rush you, etc., if they hit you before you finish casting.
- Standing in the middle of the effect of a sleet storm, etc.
- Being caught by entangle or spells with a similar effect.

[Xaratherus]

DeathQuaker wrote:

Baron_Yves wrote:

I see. So the first part of the section is simply stating that when affected by certain types of spells a concentration check is needed, and the subsequent sentences go on to explain those specific types.

Is it defined somewhere what counts as 'interference'?

For instance, would the effects of a Cleric's Bane spell act as interfering with someone?-Y

As a guideline, I would suggest looking at what other situations force a Concentration check. If a spell creates such a situation, then it also forces a concentration check.

So, the other things which force a concentration check (besides the usual casting defensively) are...

- Taking damage
- Being grappled or pinned
- Vigorous or violent motion
- Violent weather
- Being entangled

So spells which might force you to make a concentration check...
- Any damaging spell if you are casting a spell that takes more than 1 standard action to cast and it hits you before you are finished, or any spell which deals continuous damage, such as acid arrow
- Standing in a field of black tentacles
- Falling victim to a gust of wind spell, if you are susceptible, or perhaps even spells which may bull rush you, etc., if they hit you before you finish casting.
- Standing in the middle of the effect of a sleet storm, etc.
- Being caught by entangle or spells with a similar effect.

I would assume that any spell that requires a saving throw to avoid or limit its effects would also precipitate a Concentration check. Having Grease cast in the square in which you're standing, for example, requires you to make a Reflex save to avoid falling; I would state that even if you make the Reflex save, you've had to actively split part of your concentration off to remain standing, so a Concentration check would be in order.