A computer game by Cliff Johnson. Originally published by Miles Computing for Macintosh in 1987, and ported in 1989 to PC. I believe an Amiga version was also released.

The plot, setting and artwork were inspired by the Tarot deck. Players followed the Fool as he roamed the lands, encountering places and people based on Tarot cards. Puzzles included word searches, crosswords, mazes, pentominos, and jigsaws, plus a number of brain teasers that defied desciption. The original Mac graphics were black and white, but ported versions were colorized.

The Fool's Errand is something of a cult classic amongst gamers, thanks to its mind-boggling complexity, beautiful artwork, and ingenious, original storyline.

The Fool's Errand is available free for download for Mac and Windows from Cliff Johnson's website:
http://fools-errand.com/01-the-fools-errand/index.htm