The winning team for the DEFCON 30 TeleChallenge is Foxbox Dialing Services

The TeleChallenge is a DEFCON contest that has been running since DEFCON 25 (2017).

The TeleChallenge is a fully immersive puzzle challenge playable only via telephone. It combines real-world clues with phreakable systems in a battle of wits and skill. While anyone with a phone can play it is not for the faint of heart. Winning requires an intense level of dedication from the people and teams playing the game.