Wall of Force: What's the skinny?

[Ferox4]

I have read previous threads about this in the past, but don't recall any final clarifications. If you are behind a Wall of Force can you cast spells (specifically, area spells) on the other side. For example, if a Cleric is behind a Wall of Force can he cast Silence on something/someone he sees on the other side?

In my mind the quetion stems from the dynamics of magic: Does there need to be unobstructed physical space between the caster and the area of effect or not?

Please advise. F4

 

[gfunk]

To cast most spells, you need a Line of Effect. This means an unobstructed path between you and the target. Wall of Force blocks Line of Effect, therefore you cannot cast spell through it. I believe it explicitly says this in the spell description.

An important exception, also mentioned in the spell text, is gaze attacks. So spells such as Eyebite would function through a Wall of Force.

 

[RangerWickett]

Bah, that's stupid. So you're saying you can't Charm Person through a window? Or mage hand something?

I'd say let 'em cast spells through walls of force, unless there's a physical effect that couldn't cross the barrier, like a lightning bolt or fireball.

 

[Piratecat]

Bah, that's stupid. So you're saying you can't Charm Person through a window? Or mage hand something?

Nope, you can't. You can't cast any spell through a window, unless it's something like lightning bolt that shatters the window and keeps going, or something like eyebite that is a gaze attack.

Sorry, but them's the rules! And I personally think they're excellent rules, too. House ruling them opens up a whole can of worms.

 

[Ferox4]

I was unclear on the definition of "Line of Effect." Some, like RangerWickett, take it to mean a visual Line of Effect while the rules indicate that it is a tangible LoE. Thanks for the clarification.

 

[gfunk]

Here's the definition of Line of Effect from the SRD:

"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 it's not blocked by fog, darkness, and other factors that limit normal sight."

There is really no interpretation involved. Glass (in the case of windows) or force (with the Wall spell) are clearly solid. Therefore spells don't go through. House rules may be applied however...

 

[Shard O'Glase]

I can't remember the rules on it and I'm too lazy to look it up, but I wouldn't stop spells that teleport things in like the summon monster spells.

 

[gfunk]

I can't remember the rules on it and I'm too lazy to look it up, but I wouldn't stop spells that teleport things in like the summon monster spells.

You are correct about Teleport-type spells. They are instantaneous Astral Travel and are mentioned as specific ways to get around a Wall of Force. However, Summon Monster spells still require Line of Effect and shouldn't go through.

 

[Shard O'Glase]

Yeah I pretty much suspected that would be the rule. But in 2e either summons as the rule could get past or we just used it as a house rule I can't remember which. For me I like our 2nd ed way so chances are I'll keep it so summon spells can circumvent a wall of force.