[Soapy]

A sign placed on an extra level will prevent you from entering it, but a closed door will not.

Doors should probably stop you from entering places.

[Neus]

EDIT: I see what you mean. You mean that if you have a sign on top of an extra level, you can't walk up it. But if there's a closed door, you can, but shouldn't because the door is in the way. Is that correct?

[Soapy]

Yes.

(This is mostly to be used with the non-opaque doors that got suggested, so we can essentially lock extra levels.)

[Neus]

Okay, you can't enter an Extra Level anymore if there's a dense object in the same tile.

[Soapy]

You can still exit extra levels like that, which isn't very important to me, but should probably follow the same thing.

[Neus]

More specifically? You can exit extra levels that have the exits blocked by doors, or you can exit extra levels whose entrance is blocked by a door?

[Soapy]

The former.

[Neus]

This has been corrected.