From Discworld MUD Wiki
A crater can be caused by an explosion, or by someone falling from a great height.
Craters can be caused by:
- A witch crashing her broomstick
- Someone Visiting a witch in midair
- Someone falling off the roof of the Drum
- A swamp dragon exploding
- Someone being meteored by a creator
One type of crater adds a line to the room's description, above the weather line:
There is a <name> shaped crater in the ground.
Or, if multiple people were involved:
There are <names> shaped craters in the ground.
If you look at them, you'll see this:
There is a large crater in the ground, as if <name> happened here recently, from a very great height indeed.
These can be caused by the aforementioned crashes, visiting in midair, or falling off of the Drum's roof.
There's another type of crater that just shows up as "a crater" in the list of items on the ground. These can be caused by exploding swamp dragons, and look like this:
This is quite a deep crater, still smoking slightly. You get a strange feeling that it might have been a creature once.