The '''Horus Heresy''', sometimes referred to as '''Warhammer 30,000''' or ''30k'', is a supplement and expansion game produced by both [[Forge World (Company)|Forge World]] and [[Games Workshop]] directly to [[Warhammer 40,000]], where you command an army of [[Forge World (company)|Forge World]] and [[Citadel Miniatures|Citadel]] models which represent either those [[Space Marine Legion#Second Founding|Loyalist]] forces who fight in the name of the [[Emperor]], or the [[Chaos Space Marine|Traitors]] who have chosen to side with Warmaster [[Horus]].{{Fn|2}}