Wall of Fire

[Lichemaster]

Would you need to see the spot wall of fire is cast on?

In my example 6 hill giants are a arrow slots (the tiny windows of a fortress that people shot out of during seiges, sorry had a brain fart and can't remember what they are called) in a fortress firing on the party, the wizard is oustside the keep and wants to cast wall of fire in the hallway were the giants are standing.
They take up the whole arrow slot and the wizard can not see the hallway, is it possible?

 

[Jack Simth]

As far as I'm aware, you need to
a) Specify where you want to place the effect
b) have line of effect to the location

He has (a) (he wants to place it aligned with the hill giants), So depends on (b) - what's the size of the arrow slit? You need one full square foot of opening to have line of effect; any castle builder that knows this will of course design arrow slits to be considerably less than that.... say, two feet tall by three inches wide (1/2 square feet) and forget line of sight, he's denied Line of Effect, and can't cast into it, even for such things as Charm Person or Charm Monster (although a Fireball can get in there with it's specific small opening exception.....)

 

[Lichemaster]

We played it like that, but it is always good to fall back on the Question later (here) and ask.
The player ended up casting it just in front of the arrow slits and come to think of it now the slits were 50 ft up in the air so would the wall fall to the ground with no floor to cast it on?
or would it hover in mid-air?

 

[Cabral]

It doesn't say whereas Wall of Stone does. So ... no idea

 

[dcollins]

The player ended up casting it just in front of the arrow slits and come to think of it now the slits were 50 ft up in the air so would the wall fall to the ground with no floor to cast it on? or would it hover in mid-air?

SRD, "Magic Overview: Conjuration":

A creature or object brought into being or transported to your location by a conjuration spell cannot appear inside another creature or object, nor can it appear floating in an empty space. It must arrive in an open location on a surface capable of supporting it.

 

[frankthedm]

I am thinking that a caster would have to see the floor to have the wall of fire be conjured, due to the no mid air clause in in the spell.

 

[Cabral]

I do not see any no mid air clause in the spell. From d20srd.org, Wall of Fire

An immobile, blazing curtain of shimmering violet fire springs into existence. One side of the wall, selected by you, sends forth waves of heat, dealing 2d4 points of fire damage to creatures within 10 feet and 1d4 points of fire damage to those past 10 feet but within 20 feet. The wall deals this damage when it appears and on your turn each round to all creatures in the area. In addition, the wall deals 2d6 points of fire damage +1 point of fire damage per caster level (maximum +20) to any creature passing through it. The wall deals double damage to undead creatures.

If you evoke the wall so that it appears where creatures are, each creature takes damage as if passing through the wall. If any 5-foot length of wall takes 20 points of cold damage or more in 1 round, that length goes out. (Do not divide cold damage by 4, as normal for objects.)

Wall of fire can be made permanent with a permanency spell. A permanent wall of fire that is extinguished by cold damage becomes inactive for 10 minutes, then reforms at normal strength.

Arcane Material Component
A small piece of phosphorus.

Seems like fair use of the spell to me ...

 

[shilsen]

SRD, "Magic Overview: Conjuration":

Good thing Wall of Fire isn't a conjuration then, isn't it ?

 

[0-hr]

An otherwise solid barrier with a hole of at least 1 square foot through it does not block a spell’s line of effect. Such an opening means that the 5-foot length of wall containing the hole is no longer considered a barrier for purposes of a spell’s line of effect.

So as long as the arrow slits were big enough (and they most likely are), they would not stop line of effect.

 

[Infiniti2000]

So as long as the arrow slits were big enough (and they most likely are), they would not stop line of effect.

They would if the line of effect to the origin of the wall of fire did not go through them. In other words, normally the arrow slits are high, not enabling you to see the floor beyond them. You could therefore not place the wall of fire beyond the arrow slits except in the air (which is probably okay). You still have to have line of effect to the grid intersection where you want to place the wall of fire (it need not be on ground).