From the back cover:
PIECES OF EIGHT expands upon the original rules for SKULL AND CROSSBONES and is intended for use with that game. Many of the additional rules sections are not hard and fast rules, but rather are recommendations and discussions of subjects for the Game Master. In many cases it is better for the Game Master to make rulings when many factors can enter into a ruling than to attempt to detail long and complicated rules to cover the almost limitless factors that can enter into a ruling.
Some of the new rules sections, such as the rules on voodoo, are optional and are intended to be used by Game Masters with a liking for the fantasy element of fiction. Those familiar with Robert E. Howard's Black Vulmea will immediately understand how and when to apply these rules and recommendations.
Finally, PIECES OF EIGHT includes three complete adventures plus outlines for further adventures. Also included with the adventures is a map of Port Royal (not the historical city but the simplified version from the designer's campaign) with a description of the buildings and some of the inhabitants. A similar map of a smaller city, Fort de France, the port city of Martinique is also included. These descriptions give the Game Master some ideas of how to construct and populate some of the other towns which are mentioned on the SKULL AND CROSSBONES map and, hopefully, will generate other adventures using them as a basis. Though we have said it before, it still warrants mention that no rules are cast in bronze and any of them can be changed by the Game Master to vary the adventures, but care should be taken when doing so.