Expansion rules for the D&D Basic and Expert Sets.This is set #3. To be able to play the companion set, tou should already have played both, D&D Basic Set and D&D Expert Set. For character levels 15-25.Players Companion - Featuring rules for unarmed combat, strongholds, and new weapons and armor. Plus more advanced rules and spells or your characters. Dungeon Masters Companion - New rules or ruling realms and the clash of kingdoms. New treasures and monsters. Plus new adventures for your high-level characters.