Horus Heresy is a one of the early 1990's Games Workshop wargame series. It is a hex/chit type wargame involving the famous historical battle of the Warhammer 40k universe. It is the battle that occurs on Holy Terra between the traitor Warmaster Horus with his chaos followers and the Emperor and his Imperial armies. Specifically not Re-implemented by: Horus Heresy (2010)