Johnny Hart's B.C. characters star in this one or two-player action / adventure that goes heavy on humor without sacrificing challenge or excitement. Programmer Chuck Benton has translated all of the comic strip's considerable charm to the electronic game screen using graphics that will certainly please all Hart fans in the audience.

The player uses the joystick to steer Thor, mounted on his stone age unicycle, through a multi-screen panorama on a mission to rescue the Cute Chick from a dinosaur. And though the various menaces - such as the club-wielding Fat Broad - are handled with a feathery light touch, they're no less deadly. Pushing the stick north makes Thor's cycle jump, pulling it south causes the caveman to duck, and left and right movements regulate the speed. The faster Thor gets through the obstacles, the more points the gamer scores. The cumulative effect of acceleration is to move the character toward the right edge of the display, which makes it much harder to see the on-coming terrain quick enough to jump or duck as required. Happily, the program contains the solution to this dilemma: it has four skill levels. The higher the level, the faster Thor travels and the higher the speed he can maintain without drifting over to the right. In other words, once a gamer notices that he or she can get Thor moving at higher-than-minimum speed, changing to the next skill level may actually make some aspects of the contest easier instead of harder.

Quest for Tires will inevitably be compared to Smurf Rescue (ColecoVision) because both are action adventures with a similarly light-hearted ambience. The play in Sierra On-Line's game is much more fluid, since there is no need to stop to carefully line up each jump nor to bounce up and down to increase the height of the leap. And although Tires should be as appealing as Smurf Rescue to youngsters, adults are apt to derive much more enjoyment from the Sierra On-Line disk.

One small defect in Quest for Tires is that it starts much too abruptly. The first action screen comes up with no preamble of any kind, and it's frustrating to watch Thor trip on a rock or log before the player can twitch a finger on the joystick. A little theme music to announce the start of play, and perhaps a few seconds' hesitation before the on-screen animation gets going in earnest, would cure this defect.

Humor pervades the program from start to finish, making it fun as well as challenging. And watching Thor's comical pratfalls even takes a little of the sting out of failure. Overall, Quest for Tires is a polished gem, brilliant and beautiful.