Brumbaer has published AncientMaster, a free set of add on rules for Games Workshop’s Warmaster. There also are a number of army lists and links to other sites.
John Martin has written a set of free wargames rules for the American Civil War based on Games Workshop’s Warmaster. I think that things have come full circle here, because Warmaster obviously took much of its inspiration from the seminal ACW rules set, “Fire and Fury.” Not that GW would ever admit that. After all, according to the Evil Empire, miniature wargaming is the “Games Workshop Hobby”, which precludes the acknowledgement of any other rules set or miniatures.
Herbert Wong written “March to the Sound of the Guns,” a Napoleonic wargame that is a variant of Games Workshop’s Warmaster miniatures rules. Warmaster is a generally good set of rules that borrows heavily from Fire and Fury and some other historical sets. Of course, Games Workshop would never admit that. Heck, they don’t even admit that there is a miniature wargaming hobby outside of the “Games Workshop Hobby.”
Games Workshop’s Warmaster has shown itself to be a remarkably versatile set of rules. There is a Yahoo Group that is dedicated to porting the basic rules over to a wide variety of historical periods. Even better, the group’s files section has modifications for periods such as: The American Civil War, Dark Ages, Franco Prussian, Napoleonics, Renaissance and World War II.
The League of Ordinary Gamers offers sets of print-and-play counters for playing Warmaster Ancients without the investment of time and money. Their latest is a set of counters for Late Romans.