Magnus, for once, misinterprets Galahad's meaning as being about making sure others can take care with this door. He turns the knob of the door again -- mostly trying to see if there's some kind of locking mechanism, so that nobody stumbles across it by accident -- but it swings right back open again instead.

The chasm is gone. Instead, behind the door, is a government cheese cave.

"Huh." With trepidation, Magnus pokes a toe onto the floor. It's not an illusion: his foot doesn't sink through it.