Challenges are a system introduced to DROD with DROD 5.0, and was later added to previous versions of DROD. It is a script command that unlocks an achievement upon doing a specific task, such as not turning your sword or clearing a room in a certain number of turns.
Trivia
- On Steam versions of the games, clearing a challenge unlocks achievements related to them.
- Oddly, they remain unlocked on steam even if you re-lock them in the hold; and vice versa.