Horus Heresy is an out-of-print collectible card game originally produced in 2003 by Sabertooth Games. The game is set in the Warhammer 40,000 fictional universe developed by parent company Games Workshop. It attempts to recreate the struggle between the Loyalist forces of the Emperor of Mankind and the Traitor forces of Warmaster Horus, during the civil war known as the Horus Heresy. The game's development and sale by the publisher were discontinued in 2008, following financial difficulties at the parent company. History The original game package (Base Set) was released in 2003. The starter pack included several decks, rulesets for the opposing sides, and a variety of accessories and components. Promotional foil cards were also produced, as well as "story cards" that describe the background. Following the game's English language release, versions in other languages were also sold. Booster packs and other companion products were released in the years that followed; the last such set was published in 2005. The game ruleset and mechanics were designed by Ryan Miller and Luke Peterschmidt. The cards and foils were illustrated by a number of artists from Sabertooth Games' art and design department; background text was provided by Games Workshop writers. The game is set during the Horus Heresy, a galaxy-wide civil war and cornerstone event of the far future fictional universe that is the campaign setting of Games Workshop's Warhammer 40,000 wargame system. The war is set in motion by Horus, previously Warmaster (supreme military commander) of the Imperium of Man and favorite of the Emperor. The setting for each game set (base or expansion) is limited to a single significant battle or confrontation in the Heresy conflict. However the sets as a collection broadly cover the entire span of the campaign, from its earliest major battle to the final confrontation. The illustrations, annotations, and text provided new information on the Horus Heresy in general; the art joined previous work (in other Horus Heresy products) as the event's initial established imagery. Both art and story text were reproduced in later Games Workshop products. Following the sale of most Sabertooth Games assets by parent company Games Workshop in 2008, further development or sale of the game and related products was discontinued. Gameplay overview A single game of the Horus Heresy Base Set features two commanders and their respective fleets and armies struggling over control of a planet. The attacker and defender fight for