Need help with breaking a wall

Kamoj

So, I copied my cave to the wall level and changed the thickness and such to create a cave wall, but now I have this section where it's supposed to be attached through a cave it to a dungeon structure, and I can't seem to figure out how to remove the wall. I need to remove the brown section between the two grey sections. I've tried breaking, splitting, trimming, and I just can't get it to work, and exploding it creates a big mess. Any help would be appreciated!

Loopysue

You can use the break tool on the left toolbar. Click the tool, then click on the line to be broken on the part that is to be kept, then click both the ends of the bit you don't want.

It helps if those two room wall ends are snapped to the snap grid. If they are you can use the snap grid to break the cave wall.