Changes
From Warhammer 40k - Lexicanum
→Horus Heresy
After the announcment of Horus's treachery and the destruction of [[Istvaan III]], the Emperor comissioned seven Legions of [[Space Marines]] to destroy his former son and friend. But among those seven Legions, four were already traitors.
The initial landing force fell into a trap and despite their martial skills, the three loyal legions had to start a tactical withdrawal toward their landing site, which was fortified by the four traiter traitor legions forming the second wave. At this moment the second wave opened fire on the retreating Marines, crushing them between the Hammer of Horus's forces and the Anvil of the fortified Drop site. The three loyal Legions were practically destroyed despite an heroic defense and all but a handfull of battle brothers fell that fateful day.
After this awesome defeat the three betrayed Legions were unable to perform any tasks the Emperor had planned for them and spent the rest of the time of the Heresy rebuilding their forces.
