Bridging the gap between the B/X and Fifth editions of the world's oldest role-playing game, Into the Unknown is written for fans of the OSR or new school players alike. Book:1 Characters contains everything needed to create B/X style race-as-class characters for 5e games, but the specialization of the familiar 4 basic classes allows several new-school options for use with the complete rules system contained in the 5 volume Into the Unknown set.

In addition to character creation rules, the Book 1 contains an equipment sections which inlcudes old-school mainstays like henchmen while retaining new-school features such as lifestyle expenses. A simple-but-robust weapon creation and modification system replaces stock weapon list, allowing players to craft a weapon suited to their characters individual abilities.

While the steamlining of 5e is fully explained in later volumes, an appendix lists the differences between 5e and Into the Unknown in a single page, making this volume a valuable purchase for any fan of 5e.