ADVENT was the port. In shareware, you can find versions called "Colossal Cave".

XYZZY was the original name of the game, and by some accounts, the original computer game, even older than Wumpus or the ASCII versions of "Star Trek."

The name, as well as the magic word, is a common mnemonic device for remembering how to do cross products from matrix algebra.

XYZZY was originally programmed by a guy named Wille Crowther, and it found it's way to many different places, as people would get hold of it and install it on their main frames at work. There is a book "The Longest Cave" which details the history. Many of the places in the game, like "The Hall of the Mountain King" are named after actual caverns, since the original programmer was an avid spelunker.

A guy named Don Woods expanded on it quite a bit.

There are many versions of it available, even now, because once installed somewhere, people would continue to update it.

In 1978, at the tender age of 11, my mom used to take me to her office, where I got my first exposure to computers playing this game. The version I played had a wishing-well (which was also a secondary entrance to the cave), with a magic plate nearby, that would take you wherever you wanted. Whenever I tried to get to the 'city in the distance', I'd die. I never did figure out how to get to that city, and since the version I had been playing was 'customized,' I doubt I'll get another chance.

There was only one person who ever finished that particular version of the game.