Area effect "target" you can't see

[Quasqueton]

In our last game session, I ruled that you can't fire a fireball to explode inside a obscuring mist because you have to have line of sight to your target (point in space). Later, upon reading the PHB to double-check myself, it seems I may have been in error.

So, can you cast an area effect spell (such as fireball) into an area you can't see (darkness, fog, etc.)?

Quasqueton

 

[ConspiracyAngel]

PHB page 258, under Obscuring Mist, says that a fireball, flame strike or similar spell burns away the fog...

By this text I would say that they can randomly place (center) the fireball spell on any 5-ft square within or near the mist. If the enemy is hiding in an affected area of the fireball, that yes he/she/it be affected by the fireball as well minus his/her/it's dex bonus to AC, because unless they can identify the fireball spell by sound, they have no way to know what is coming.

(Note: If they select, let's say, a space 10ft within the mist, and something intercepts the tiny ball that causes the spell, then I would say it detonates 5 ft early, possibly catching themselves with the blast, should they be too close.)

(Second note: Fireball, PHB page 231, does not state that it requires any target. It says this "you point your finger and determine the range (distance and height) at which the fireball is to burst...")

 

[Len]

You need to have line of effect to the target point, not line of sight. Line of effect is not blocked by darkness, fog etc. See p. 176 in the PHB for more info.

 

[shilsen]

So, can you cast an area effect spell (such as fireball) into an area you can't see (darkness, fog, etc.)?

Yes. If there is something within the area that prevents line of effect to the point where your spell will originate, then it fails (or, in the case of a fireball, may detonate early), but simply being unable to see the point where you want it to take effect doesn't hinder the spell.

 

[Pinotage]

Also note that spreads and bursts behave differently in that the spread moves out from a point of origin and can move around corners. Hence in that case line of effect is not even required, as long as it's a spread effect.

Pinotage

 

[dcollins]

From the SRD "Magic Overview: Aiming a Spell":

Effect: Some spells create or summon things rather than affecting things that are already present. You must designate the location where these things are to appear, either by seeing it or defining it. Range determines how far away an effect can appear, but if the effect is mobile it can move regardless of the spell’s range.

So for an "effect" spell such as fireball, you can either see the targetted location OR "define" it, such as by saying "20 feet into that obscuring mist".

 

[Infiniti2000]

Does solid fog prevent a fireball?

 

[MichaelH]

Does solid fog prevent a fireball?

Good question. The spell description says it does not stop magical effects like rays and the like, so I don't think it would prevent a fireball from being targeted within the cloud. If it did do such things the spell would specifiy that.

 

[DevlinStormweaver]

In the game i am in last night our cleric was blinded, but wanted to cast a sound burst. It was ruled he couldn't. reading this post it semms like he could, but how would you rule where it went off.

 

[Len]

It goes off where he says it does. The trick is getting the player to pretend that he can't see where things are when he specifies the spell's target. If he can't keep his OOC eyes from helping his character, then the DM can do something like roll randomly to put the spell near where he wants it, or tell the player to sit facing away from the table while he's blinded.