Osiris,Horus was also like jesus in christian mithology, a real person, son of god.It is a matter of other discution are theese persones have lived ever

Sorry, but as far as I know, Horus was a mythological figure--He never really lived.
Through-out Egyptian history, when a Pharaoh came to the throne he was known as The "Living Horus", to establish his divine right to rule.

Afcourse he lived , he succeed Osiris in rulling the word of living, he was grown "hidden" in the delta of Nile so according to Egyptian mithology he lived.Here we came to point of "mythological" , so is a bible mythological also ?In my point of view Jesus is just mithological hero as is Horus.

Your keywords here are "according to mythology". In other words, he was not real, but believers thought him to be real.
Any mythological figure can be real to believers, but that in no way makes them real automatically. Because I believe in Satan, does that make him real? If I believed in the Diads (spirits who live in trees) would that make them real? If I believed in Zeus, does that make him real?

The key is that Jesus and Horus are bouth mythology people , gods halfgods or whatever, we can not say are they where such a persons or not , and that is not a matter of our discution.What we discus here is just "acording to mythology" because we have no other sourses for theese... lets say "names".
So, myth for Osiris even from "New kingdom" say that Horus was lived in earth , so it was lived here and that is it. Same whit Jesus, bible say that he was a living person , so he is.

Dont think Ive even seen any mention of the Custodes in any of the M41 books Ive read so far, but theyre quickly becoming my favorite group of the Horus Heresy timeline.