Wow 6 editions of this game. It's my favorite roleplaying system. very versatile and flexible. With 6 editions there are tons of reference and resource books. Recommended to gamers

A good succinct introduction to the excellent Hero System RPG. I read this in order to have a clear idea of the then current rules for several sourcebooks for 4th edition Hero System. This is the 4th edition of the rules published in 1990.