Fireball and LoS

[Lentrax]

Quick question. I don't think it does, but does a caster need LoS to cast a Fireball?

Just asking because a group I am running has a Fog Cloud going, and the casters need to hurl through it.

Yes or No. Does the caster need Line of Sight to throw a fireball?

[Manly Man]

They don't need line of sight to throw it, but to aim at anything specific, yes. If it misses, it just goes until it reaches the farthest point in its range, and then explodes.

[Chronos]

Fireballs aren't aimed, and don't need to hit anything. You need to know what square you're centering it in, and if you can't see, you might guess wrong and not catch the enemies in the area, but it'll still go off in that square.

[KillianHawkeye]

Fireballs aren't aimed, and don't need to hit anything. You need to know what square you're centering it in, and if you can't see, you might guess wrong and not catch the enemies in the area, but it'll still go off in that square.

That is true to a certain extent. However, it's also true that the spell launches a tiny bead at the target area and that bead can explode prematurely if it hits something in the way, so there is potentially some aiming involved. The PHB even lists an example of trying to shoot the fireball past a narrow opening.

You point your finger and determine the range (distance and height) at which the fireball is to burst. A glowing, pea-sized bead streaks from the pointing digit and, unless it impacts upon a material body or solid barrier prior to attaining the prescribed range, blossoms into the fireball at that point. (An early impact results in an early detonation.) If you attempt to send the bead through a narrow passage, such as through an arrow slit, you must “hit” the opening with a ranged touch attack, or else the bead strikes the barrier and detonates prematurely.

[Diarmuid]

You need LoS and LoE for all spells unless otherwise specified.

[Jack_Simth]

You need LoS and LoE for all spells unless otherwise specified.Line-of-Sight only applies to Targetted spells. Effect or area spells only care about line of effect (although a ray, which has an attack roll, does much better when you can see your target).

[Diarmuid]

You must have LoS to the "origin" point where you wish your AoE to start from. You can't "target" a square as the "center" of your 20' radius burst if you do not have LoS to is.

[Maginomicon]

You must have LoS to the "origin" point where you wish your AoE to start from. You can't "target" a square as the "center" of your 20' radius burst if you do not have LoS to is.
That makes no sense. (http://www.giantitp.com/forums/showthread.php?t=297907) You aren't actually "targeting" the square. It's just the origin.

[Diarmuid]

I was under the impression that this bit supported my stance:



Area

Some spells affect an area. Sometimes a spell description specifies a specially defined area, but usually an area falls into one of the categories defined below.

Regardless of the shape of the area, you select the point where the spell originates, but otherwise you don’t control which creatures or objects the spell affects. The point of origin of a spell is always a grid intersection.


...but upon reading further it does not seem to be as supported as I remembered,



You must have a clear line of effect to any target that you cast a spell on or to any space in which you wish to create an effect. You must have a clear line of effect to the point of origin of any spell you cast.


My problem with this is playing on a map where a "character" cannot see through a fog 50 feet from him, yet can properly target a fireball to catch as many of the enemies the "player" can see on the map as possible.

My group has seen it done too many times and I think that's probably why my group also instituted the LoS rule for establishing PoO for area spells, but that's clearly our houserule.

[ericgrau]

Well if you don't know where the enemies are in the fog that could keep you from a perfect fireball too. As a house rule you might also institute a 50% chance that your target is off by a square (roll a d8 for direction), to keep from overly precise targeting in a fog. But I think you should certainly be able to put the orange bead somewhere in the middle of the fog by both RAW and RAMS.

[Jack_Simth]

You must have LoS to the "origin" point where you wish your AoE to start from. You can't "target" a square as the "center" of your 20' radius burst if you do not have LoS to is.
You need line of effect to it, not line of sight. It's part of the Aiming a Spell (http://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#aimingASpell) section of the magic overview. In the cast of a spell with a Target line (such as Magic Missile), yes, you need line of sight. In the case of an area spell (such as Fireball), then you don't. You still need Line of Effect (at least to the center of the Fireball), but not Line of Sight.

[Feint's End]

As mentioned before I say that fireball doesn't need line of sight to the centre but you have to specify where it should explode (basically like shooting blind). And I do believe RAW supports me there. Since you specify height and range of the "missile" you can basically shoot it completely blind ... now if you will hit anyone is another story ...

My group usually handles it this way: make a spellcraft check against a dc set by the DM. If you succeed the fireball hits the field ... if you don't it shifts into a random direction depending on how much you failed.

But then again. I also say you don't even need to have LoE for some centred spells like entagle.

[Maginomicon]

But then again. I also say you don't even need to have LoE for some centred spells like entagle.
I would agree with you there (http://www.giantitp.com/forums/showthread.php?t=297907) except for the idea of "I want to entangle the area beyond this wall", which doesn't make sense to me.

[Lentrax]

Okay, so let me add some specifics to the situation.

The group is fighting a Drow border outpost. The time is currently 3ish in the morning so it is completely dark. The entire party is lit up by their campfire behind them, but they have remained stock still. Maybe two of them have used a 5ft step.

The party gets the idea to cast a fog cloud in front of them to give them concealment. Which is what brings me to my question.

If LoE is all I need, then the Drow wizard can fire his fireball where he last recalls the knight being.

Something like this?

[SPoilaaja]

Snipped


The first quote talks about selecting and the second about targetting. selecting is not targetting by raw.

[ericgrau]

Okay, so let me add some specifics to the situation.

The group is fighting a Drow border outpost. The time is currently 3ish in the morning so it is completely dark. The entire party is lit up by their campfire behind them, but they have remained stock still. Maybe two of them have used a 5ft step.

The party gets the idea to cast a fog cloud in front of them to give them concealment. Which is what brings me to my question.

If LoE is all I need, then the Drow wizard can fire his fireball where he last recalls the knight being.

Something like this?

Yes he can. If the knight is still there he'll get hit. If not he won't. Concealment isn't that useful against area of effect spells. It does help a great deal against arrows, ray spells and targeted spells though. Or even spells with a small area like glitterdust because the whole party including the fog maker can easily move back or forward 30 feet. It just doesn't help much against 40 foot across monstrosities like fireball. You might as well be throwing the broad side of a barn at your target.

[Lentrax]

Thank you.

And now I know my next homebrew spell: Broad side of a barn.

[Manly Man]

Thank you.

And now I know my next homebrew spell: Broad side of a barn.

http://i.imgur.com/SCRMTPm.jpg