Cutting Holes in terrain

I looked as far back as page 15 in these forums to find out if there were any topics posted about this, but I only saw two. One where a guy was asking why the terrain pops back into the hole after he cuts it, and one where a guy asked this very question, but I was the only one who answered and at the time, I didn't know that you actually could cut holes in the terrain. So, I ask again. How the heck do you cut holes in the terrain?

I'm trying to create a level where part of it is underground. My thoughts on how to create this effect would be to either make a canyon in the terrain, place the nderground part in the gap, make the terrain on top of the underground part in World Craft and then try to blend the rest of Torque's terrain to fit with the hand made terrain in WC. The problem with this is that to create some nice terrain in WorldCraft I'd have to use away too many polys.

So the second idea I had was to simply put the underground room underneath the terrain in torque, but have the two spiral stairs sticking out through holes in the terrain. Problem is, I have no clue how I'd actually cut holes in the terrain.

Can anyone help me out with this?

Thanks!

-Peter Ryan aka TorQue[MoD]
Project Lead
Brutal
www.surrogateinteractive.com