Is there a spell for this?

[ksbsnowowl]

Wait for the avalanche, Passwall!

Planar Ally a Blue Slaad and he can use Passwall at will.  The only issue you run into is that passwall only works on a wall, not a jumbled pile of stone.  Nothing in Passwall says it shores up the overhead materials... mine cave in, anyone?

Darn, Planar Ally takes an 11th level Cleric...

[SorO_Lost]

Nothing in Passwall says it shores up the overhead materials... mine cave in, anyone?

Dig a 10ft hole, Passwall!

[ksbsnowowl]

Nothing in Passwall says it shores up the overhead materials... mine cave in, anyone?

Dig a 10ft hole, Passwall!

Now that's an idea.

What my PC's did (albeit up around 14th level) was disintegrate a 10-foot pit into the stone ground, then start using passwall and phase door for various purposes.

It would slow down the advance of the caravan, but it would be doable.  Sadly, it is above the abilities of a 5th level Wizard.

[SorO_Lost]

Sadly, it is above the abilities of a 5th level Wizard.

Oh 5th level? Yeah, spamming Passwall! is kind of out of the question.