The PC can repeatedly fall into a pit by '\Ct'riggering it
By using the command to '\Ct'rigger a trap, it's possibly to fall inside the pit you're already on.
Problem
"While staying on top of a pit, one can repeatedly activate the trap to repeatedly fall into the pit, without having to climb out." -- sorear's wiki
How to reproduce it
Find a pit trap, or dig a pit of your own. Climb out of it (if applicable), then step back into its tile and press Ctrl+T repeatedly. You'll always fall, even though you're already inside it.
Notes.
When triggering a trap, the game seems to check if you're on a pit when you've just dug it, but not afterwards.