[RPG] Does an internal Wall of Force limit the Tarrasque

dnd-5espells

Per an answer to this question about capturing a Tarrasque in a Wall of Force sphere, it seems the Tarrasque can use Swallow on a caster, who can then cast a Wall of Force spell inside the Tarrasque.

The description of the Wall says (emphasis mine)

Nothing can physically pass through the wall. It is immune to all damage and can't be dispelled by Dispel Magic. A Disintegrate spell destroys the wall instantly, however.

Does this mean such a Tarrasque would have its movement limited by the swallowed Wall? It seems the alternative is that it can move around a spell effect with physical force, which seems wrong to me.

Best Answer

The Tarrasque would be pushed to one side of the wall when you cast the spell:

If the wall cuts through a creature’s space when it appears, the creature is pushed to one side of the wall (your choice which side).

If you cast the wall inside the beast, it clearly "cuts through a creature’s space when it appears", and therefore "the creature is pushed to one side of the wall".

Of course, at that point it wouldn't hinder the creature's movement much.

Regarding how this should be narrated by the DM, there isn't much to go on in the spell's description.

For example, what if the wizard shapes the wall into a sphere around himself? This is such an unusual situation, so the DM would have quite a bit of latitude in determining how the result is narrated.

It is fun to imagine that the wizard, in a giant bile filled snow globe, is unceremoniously ejected from the Tarrasque like a hairball from a cat. I'm not sure who comes out ahead in that scenario.