There's a blackjack tournament coming up soon. Find a strategy to win 27 rounds in a row to get the flag.
[rough description from memory, as the challenge pages were taken down after the CTF]
Relevant files available here : https://drive.google.com/folderview?id=0BwkgkWPmhQZsYk1tVWtDVDNackE&usp=sharing
|Ba Sing Sec