I came across a really old kotaku post where it talks about a discovered glitch which really brakes the game. The glitch gives you the blackjack airship really early in the game after you get Locke and Terra out of narshe. In order to perform this exploit, you have to do the following:

- Make 2 saves at the point where you get Terra and Locke out of Narshe for the 1st time.

- Play on the 2nd file until you unlock the floating continent without saving or dying even once.

- When you have the opportunity to find the floating continent, choose lift off instead and fly around for 30 seconds.

- When you finished flying around, go to the wheel again and choose find the floating continent and play through the event that gets you on the floating continent.

- Have your party get killed on the floating continent and it will jump you back to outside of narshe with locke and terra and you should have the airship if you did everything correctly.

Here's an article that tells you how to do it if you didn't get the instructions.
How To Break Final Fantasy VI