Under Horus' direction, [[Leman Russ]] and his [[Space Wolves]] travelled to the homeworld of [[Magnus the Red]]'s [[Thousand Sons]]; [[Prospero]]. Russ had been charged, by the [[Emperor]], with retrieving Magnus back to [[Terra]] on charges of practising sorcery and thus going against the decisions made at the [[Council of Nikaea]]. Upon Russ's arrival on Prospero he showed no intention of making a peaceful arrest [supposedly due to Horus' persuasions] and commenced the bombardment and subsequent invasion of Prospero. Prospero Burns will cover this incident.