Plexiglass Fort Knox Pro Box. Escape Welt. Can you invade the impenetrable Plexiglass Fort Knox Pro Box and take ownership of the hidden Bubu coin? In order to locate the valuable relic, you'll have to overcome a number of obstacles and riddles to gain access to the vault. Do you have what it takes to uncover the secrets of Al Capone? Twist, slide and decipher your way through your "ice glass" strongbox!