basement possible?

Hi There

I had an idea for building mechanism that you maybe come to find interessting:

I would really like a possiblity to build at least 1 floor Underground… like a Basement…

i’d be even cooler to be able to build like 10 floors Underground (like a bunker).

Thank you for your opinions on this one
Oru

There were some posts about this matter, but is appears to be impossible to implement

damn that is rather disappointing

I can’t see this being very secure. Easy to go down, hard to go up.

thats what she said

so’s that:)