D&D 3E/3.5 Rules Query - 3.5E - Line of Effect for Spells

[Olaf the Stout]

We had this situation come up in our 3.5E game last night. My PC had cast a Wall of Force between our party and some bad guys.

The Druid had cast Call Lightning and wanted to strike one of the bad guys on the other side of the Wall of Force. Here are the relevant rules that I think impacts on this situation:

Call Lightning
Evocation [Electricity]
Level: Drd 3
Components: V, S
Casting Time: 1 round
Range: Medium (100 ft. + 10 ft./level)
Effect: One or more 30-ft.-long vertical lines of lightning
Duration: 1 min./level
Saving Throw: Reflex half
Spell Resistance: Yes

Immediately upon completion of the spell, and once per round thereafter, you may call down a 5-foot-wide, 30-foot-long, vertical bolt of lightning that deals 3d6 points of electricity damage. The bolt of lightning flashes down in a vertical stroke at whatever target point you choose within the spell’s range (measured from your position at the time). Any creature in the target square or in the path of the bolt is affected.
You need not call a bolt of lightning immediately; other actions, even spellcasting, can be performed. However, each round after the first you may use a standard action (concentrating on the spell) to call a bolt. You may call a total number of bolts equal to your caster level (maximum 10 bolts).
If you are outdoors and in a stormy area—a rain shower, clouds and wind, hot and cloudy conditions, or even a tornado (including a whirlwind formed by a djinni or an air elemental of at least Large size)—each bolt deals 3d10 points of electricity damage instead of 3d6.
This spell functions indoors or underground but not underwater.

Line of Effect
A line of effect is a straight, unblocked path that indicates what a spell can affect. A line of effect is canceled by a solid barrier. It’s like line of sight for ranged weapons, except that it’s not blocked by fog, darkness, and other factors that limit normal sight.
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.
A burst, cone, cylinder, or emanation spell affects only an area, creatures, or objects to which it has line of effect from its origin (a spherical burst’s center point, a cone-shaped burst’s starting point, a cylinder’s circle, or an emanation’s point of origin).
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.

Wall of Force
Evocation [Force]
Level: Sor/Wiz 5
Components: V, S, M
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Effect: Wall whose area is up to one 10-ft. square/level
Duration: 1 round /level (D)
Saving Throw: None
Spell Resistance: No

A wall of force spell creates an invisible wall of force. The wall cannot move, it is immune to damage of all kinds, and it is unaffected by most spells, including dispel magic. However, disintegrate immediately destroys it, as does a rod of cancellation, a sphere of annihilation, or a mage’s disjunction spell. Breath weapons and spells cannot pass through the wall in either direction, although dimension door, teleport, and similar effects can bypass the barrier. It blocks ethereal creatures as well as material ones (though ethereal creatures can usually get around the wall by floating under or over it through material floors and ceilings). Gaze attacks can operate through a wall of force.
The caster can form the wall into a flat, vertical plane whose area is up to one 10-foot square per level. The wall must be continuous and unbroken when formed. If its surface is broken by any object or creature, the spell fails.
Wall of force can be made permanent with a permanency spell.

Material Component A pinch of powder made from a clear gem.

My reading of it is that the Wall of Force blocks Line of Effect (but not Line of Sight). Therefore you can't Call Lightning on someone on another side of a Wall of Force.

The only argument I could see disputing this is that, unlike a regular line spell, the lightning does not originate from the caster. It comes from above. So the point of origin for the lightning is the same side of the Wall of Force as the target, so the Wall of Force does not block Line of Effect.

However, the rules for line of effect specifically state

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

Which I think stops you from even using something like Call Lightning.

Thoughts?

 

[captnq]

If you want to block both line of sight and line of effect, you use Darkway. It's a force bridge you can't see through. Great for screwing with chargers, targeting spells, and various other dangers.

Now, the wall of force, is it in wall form, or a dome?

If it's a vertical wall, does no good.

Call Lightning
Effect: One or more 30-ft.-long vertical lines of lightning

The wall would stop a bolt of lightning originating from your hand. Good old fashioned Lightning bolt is useless against a Wall of force. But Call lightning is basically a cylinder that's 5 feet in diameter, 30-feet high. Which is basically a vertical line.

Now if the wall of force was a dome, or placed at a 45 degree angle and the target was standing under it, then the spell fails. Call lightning, Flame strike, and other cylindrical/death from above spells are used specifically for that targeting purpose. To put an end run around the Transparent nature of Walls of Force, so you have line of sight, then have line of effect from a direction that ignores the wall by having the point of origin somewhere behind it.

 

[Olaf the Stout]

The Wall of Force was shaped as a wall.

The one bit I missed out is that the Wall of Force completely blocked a stone passageway. So it was a 20ft wide by 30 foot high passageway that was covered by a Wall of Force.

I understand what you're saying about Call Lightning. It was what made us unsure. Something like a ray or a fireball is easy to rule on since it originates from the caster. However, Call Lightning does not. The bolt of lightning originates from a point different to the caster.

However, the rules for line of effect specifically state:

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

So the counter argument is that you're creating an effect on a space which you don't have line of effect to. i.e. You can't choose a point of origin for the Call Lightning on the other side of the Wall of Force as you don't have line of effect to that area.

 

[delericho]

My reading of it is that the Wall of Force blocks Line of Effect (but not Line of Sight).

Yep.

Therefore you can't Call Lightning on someone on another side of a Wall of Force.

I believe this is correct. However, I would recommend checking the "Rules Compendium" - it says a few things about spellcasting, and line of effect specifically, which were at odds with my understanding. (I lost an argument about antimagic and line of effect a couple of months ago. )

The only argument I could see disputing this is that, unlike a regular line spell, the lightning does not originate from the caster. It comes from above.

While that's true, I believe you need line of effect to the point "above" from which the lightning appears. So call lightning can't hit a target on the other side of the wall of force because you don't have LoE to the point at which the bolt would appear.

(Though if the WoF didn't fill the whole height of the corridor, you could potentially have a bolt appear directly above the wall and then arc down to the target, just as you might throw a rock to hit them.)

Maybe. As I said, I recommend checking the RC.

 

[Greenfield]

First, Wall of Force can't be shaped into a Dome any more. That ended with 3e. 3,5 doesn't allow that.

Second, I agree that you need Line of Effect to at least the start point of the Call Lightning, and ideally to the actual target point on the ground.

So, whether there is a LOE to the start point is a matter of geometry: How tall is the wall, and how close is the Druid? How far away is the target zone?

Easy check: Draw the line where the WoF is. Measure up the height of the wall, two inches per WoF segment (WoF comes in 10 foot squares.) Now use a straight edge from the mini to and over the top of your "wall". If the spot over the target is more than six inches above the board (30 feet) then he can't Call Lightning on that target at this time. He/She either has to move back to improve the angle, or maneuver around the Wall.

One final note: WoF is invisible, so the Druid can't actually tell if it's in the way unless he/she has some way to know where it is.

 

[captnq]

First, Wall of Force can't be shaped into a Dome any more. That ended with 3e. 3,5 doesn't allow that.

Customized Wondrous Item created with DM permission
Various Metamagic combos to shape the spell and create a dome.

I remember a combo involving turning a wall into a single target, then ranged, then a ray, then ray into a cone, then sculpt spell to do something really weird, but frankly, I don't have the time to look it up.

You can do ANYTHING in 3.5 if you put your mind to it.

 

[Rabulias]

Various Metamagic combos to shape the spell and create a dome.

I don't think anything in official D&D 3.5 will do this. The Sculpt Spell metamagic feat in 3.5 would not affect a wall of force; Sculpt Spell only affects Area spells and wall of force is an Effect spell.

 

[Olaf the Stout]

First, Wall of Force can't be shaped into a Dome any more. That ended with 3e. 3,5 doesn't allow that.

Second, I agree that you need Line of Effect to at least the start point of the Call Lightning, and ideally to the actual target point on the ground.

So, whether there is a LOE to the start point is a matter of geometry: How tall is the wall, and how close is the Druid? How far away is the target zone?

Easy check: Draw the line where the WoF is. Measure up the height of the wall, two inches per WoF segment (WoF comes in 10 foot squares.) Now use a straight edge from the mini to and over the top of your "wall". If the spot over the target is more than six inches above the board (30 feet) then he can't Call Lightning on that target at this time. He/She either has to move back to improve the angle, or maneuver around the Wall.

One final note: WoF is invisible, so the Druid can't actually tell if it's in the way unless he/she has some way to know where it is.

My Wall of Force was definitely a wall. It covered the entire 20ft wide x 30ft tall passageway.

Good point about the wall being invisible. However, there were about 6 baddies pressed up against the other side of the wall, which would have given the druid some indication that there was something blocking the way. The druid also knew I could cast Wall of Force, so you could argue that he put 2 and 2 together to figure out what had happened. In any case, the meta-knowledge wasn't an in-game issue.

 

[Greenfield]

Customized Wondrous Item created with DM permission
Various Metamagic combos to shape the spell and create a dome.

I remember a combo involving turning a wall into a single target, then ranged, then a ray, then ray into a cone, then sculpt spell to do something really weird, but frankly, I don't have the time to look it up.

You can do ANYTHING in 3.5 if you put your mind to it.

Sculpt Spell won't turn a Wall into a Dome. Or a Cone into a Dome. Or a Ray into a Dome.

If you want domes, use Resilient Sphere or Telekinetic Sphere.

You can find anything in 3.5, if you look hard enough.

 

[Greenfield]

I've been thinking about the "Wall to Single Target, to ranged, to ray, to cone, to dome" thing.

Presuming that all of these metamagic feats exist (I know that some of them do), the spell level is still an obstacle.

1) Wall of Force is a 5th level spell. Wands go up to 4th level.
2) The "Reach Spell" feat, which turns touch spells into ranged touch spells, adds 2 levels to the required slot. We're up to 7
3) The Sculpt Spell feat, which can turn an area like a cone into a ball, adds 1 level to the required spell slot. We're up to 8.

Presuming these other metamagics that I've never heard of follow the standard pattern, "Wall to single target" would take the spell level to 9, and "Ranged Touch" to "Ray" would make it 10. "Ray to Cone" would make it spell level 11.

See the problem? Aside from the idea of putting a spell level 5+ in a wand, it ends up being an Epic spell, which means an Epic item.

Why not just say, "We kept the 3.0 version of the spell in our game."? So much easier than the rules gymnastics you described, and involves far fewer house rules.