In the mid-1980s, a small company called Mark Data Products released 6 parser-based graphical adventure games similar to early Polarware and Scott Adams titles. While the games were reasonably successful on Tandy's CoCo computer, the IBM PC versions did not achieve the same level of success. While the graphics were quite good at the time, the parser is quite primitive - only simple verb+noun constructs such as GET HAT are understood, and some verbs that are common in IF games such as SEARCH are not always recognized. Fortunately, the games make up for the primitive parser with a well-written plot, fun characters, and some clever puzzles.
The plot of Calixto Island: "A valuable treasure has been stolen from a museum; can you recover it? Calixto Island is a challenging puzzle with an occasional twist of humor. You'll visit a laboratory and a Mayan pyramid, and meet crazy Trader Jack - all in living color and exciting detail."
Thanks to the generosity of Bob Withers, co-creator of these underdogs who put both the games and their source codes up on his website for free downloading, you can now experience a forgotten past of the early days of adventure gaming. They're all recommended, but if you want the best of the bunch, I highly recommend my personal favorites: Trekboer and Calixto Island. Reviewed by: Underdogs