CTF arena
Rooms with per-user flags and a scoreboard that means something
Every flag is derived per user, per challenge, per season by keyed HMAC and is never stored anywhere. A flag pasted into a group chat is worth nothing to whoever receives it.
Rooms
Open rooms
How it works
The rules of the arena
Flags are yours alone
Derived per user per challenge per season, never persisted. Sharing one does not transfer a solve, so the scoreboard reflects who did the work.
No guessing is rewarded
Rooms are built so that no challenge is solvable by brute force or by guessing a path. If you are guessing, you have misread the room rather than found a shortcut.
Hints cost nothing but points
Every challenge carries progressive hints. Taking one reduces the points for that challenge and never blocks progress, because a learner stuck for an hour has stopped learning.