The Junior General offers a set of fast play rules as well as paper figures for the Battle of Granicus, in which Alexander The Great took on the Persian Empire.
Advanced Virtus is a set of free wargames rules for ancient warfare. They’re described as “fast and furious.”
Ancient Combat is a set of free wargames rules by Matt Cappetta.
Legio Wargames offers Legio VI Macedonia, a set of free wargames rules for playing games set in the Helenistic through the Republican Roman eras. They’e designed for 6mm figures, with one 20mm x 20mm stand equaling 300 – 500 heavy infantry.
Legio Wargames offers Legio VI Julia Augusta, a set of free wargames rules for battles of the late Roman Republic and Empire (100BC to AD250). They’re designed for 6mm, where one 20mm x 20mm stand equals a cohort.