Changes

It has been speculated that the reason for there being 2 two [[Primarchs]] of the Alpha Legion is due to Chaos 'mutation'. When the [[Chaos Gods]] scattered the Primarchs across the galaxy in order to prevent the [[Emperor]] conquering the galaxy, the infants were dragged through the warp and ended up landed on seemingly random planets across the galaxy. [[Magnus the Red]] was effected by the warp in that he spawned a third eye, and could have even gained his grand psyker abilities from the warp during this time (although he may have gained these abilities from the [[Emperor]]). [[Sanguinius]] was also subject to corruption in that he gained angelic wings. Mutation in this sense effected at least 2 two of the [[Primarchs]], therefore Alpharius could have been subjected to similar mutation (similar to when twins develop) and could have seperated him into two bodies (Alpharius Omegon). If taken in context; "One soul in two bodies"*¹ can also support this theory. The fact that the Emperor seemingly didn't know about Omegon also reinforces this theory, as he would'nt have been aware of the mutation which occured in the [[warp]].

If the [[Horus Heresy]] novels are taken to be canon then this would technically bring the number of [[Primarchs]] to 21. It is unlikely that Omegon could be one of the 'Missing' [[Primarchs]] as it can't be explained why he was already united with Alpharius prior to being discovered by [[Horus]]. If Omegon is the 21st [[Primarch]] then the [[Emperor]] would have been aware of him, as he would have been created by the [[Emperor]].