Board Thread:Warhammer 40k General Discussion/@comment-24405075-20150318130307/@comment-24405075-20150322133929

@ the C"tan theory. yes they have a consciousness but that doesn't nessecarily mean they will influence the warp remember there are beings called pariahs. also from the article " ''The primary weakness of the C'tan is their inability to comprehend the Warp. It is speculated that they find it impossible to survive in it and are particularly susceptible as a result to Warp-spawned psychic and the psykers that wield it''" from what we can tell the warp is a sort of poison to them and they actively repel it. from this we can infer that they are beings that can only exist in realspace. conversly deamons can only exist in realspace as long as there is an active connection to the warp ex warp rift, warp storms.

@ the grey knight theory. yes the being would be inexperienced but it can still learn and the library in Titan holds one of the most  extensive in knowledge concerning the warp. whats more we know that primarchs learn and mature quickly. whats to stop the new being who is infintly more powerful in every way

@ primarch theory it is never stated they were eradicated or killed just erased from records. Even against Horus the emperor was reluctant to kill him. whats more while he had no qualms using 1 legion against another ex wolves vs Sons.however  He didnt order russ to kill magnus only to capture and bring him to terra. SO we can see that there is a higher chance of the primarch to be imprisoned than to be killed. even if he was killed we can still use m theory to explain the deathwatch and fortress enrioch and instead in the deepest vault is either the body of the primarch, the truth on what happened, or the geneseed of the lost legion. all of the above can explain " the final bastion is truth" about the deathwatch anyway