jaelis said:
A brick wall is a solid barrier that would stop sound attacks, but you can still make a listen check through it.
A brick wall is not impervious to the equivalent of a nuclear explosion.
We do not really know what force is or does (outside of incorporeal creatures). The main thing we know is that in the case of Wall of Force and Force Cage, it stops spells and creatures from passing through them and in the case of a barred cage, it stops larger weapons as well.
That's most of it. Most everything else is conjecture.
This powerful spell brings into being an immobile, invisible cubical prison composed of either bars of force or solid walls of force (your choice).
Creatures within the area are caught and contained unless they are too big to fit inside, in which case the spell automatically fails. Teleportation and other forms of astral travel provide a means of escape, but the force walls or bars extend into the Ethereal Plane, blocking ethereal travel.
Like a wall of force spell, a forcecage resists dispel magic, but it is vulnerable to a disintegrate spell, and it can be destroyed by a sphere of annihilation or a rod of cancellation.
Barred Cage: This version of the spell produces a 20-foot cube made of bands of force (similar to a wall of force spell) for bars. The bands are a half-inch wide, with half-inch gaps between them. Any creature capable of passing through such a small space can escape; others are confined. You can’t attack a creature in a barred cage with a weapon unless the weapon can fit between the gaps. Even against such weapons (including arrows and similar ranged attacks), a creature in the barred cage has cover. All spells and breath weapons can pass through the gaps in the bars.
Windowless Cell: This version of the spell produces a 10-foot cube with no way in and no way out. Solid walls of force form its six sides.
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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.
Nowhere in the description of Wall of Force does it state that it stops material objects. The wall itself cannot be harmed or moved, but that says nothing about it being solid and stopping other material objects.
So, if one rules literally that since Wall of Force does not state that it stops sound, then one should also literally rule that it does not stop rain, or arrows, or normal fire, or wind, or natural lightning from the sky, or smoke from a Smokestick or the goo from a Tanglefoot bag, etc. If one were to rule literally.
Given the descriptions we have, I prefer to rule that both spells stop everything (in the windowless cell version of Force Cage). Matter. Energy. Magic. Sound. Everything. The only thing they do not stop is Light (because they are invisible), Gaze Weapons, and Teleportation Magic. Note: Force Cage does not state that Gaze Weapons go through it, but that is a personal ruling of mine that both spells work identically in that case since I like consistency.
Instead of ruling that only the things it stops is the things that it explicitly states that it stops (which leads to Walls of Force not stopping rain or the heat of a forest fire whereas a stone wall would), I prefer to rule that the only things it does not stop is the things it states it does not stop. I focus on the exceptions as opposed to the inclusions.
The reason I do this is that the Wall of Force spell does not state that it stops arrows or any other material object or weapon. Only the Force Cage implies that (an inference based on it being solid and on the Barred Cage version stopping larger weapons).
Additionally, neither spell explicitly stops extraordinary or supernatural abilities. For example, an Aboleth's Enslave or its Mucus Cloud.
It does not make sense to me (from a historical DND Wall of Force POV) that a Wall of Force would not stop arrows or bolts, and anything else that could pass through it. And that is what one would have to rule if one were to literally rule only based on what Wall of Force states that it stops. So, I take the opposing POV and rule that it stops everything and does not stop what it explicitly states it does not stop. I rule the same for Force Cage (actually, I rule that the spells are identical for all intents and purposes).
I find ruling in the opposite direction nebulous and arbitrary (well, Wall of Force stops arrows, but it doesn't stop sound: huh?).