Does this mean in the deception they could lose there salvation?

Like if Christian in Churches end up worshipping the Anit-christ and or also taking the mark would have there names blotted out of the book of life.

Also how about Christian the change the word of God? What happens to there name?

This is what I find so puzzling about the once saved always save crowd. They just say it is impossible to saved, or be a believer had have your name blotted out of the book of life or be renewed unto repentance, or one could blaspheme the Holy Ghost after being saved, or simply just quit believing, they just skirt the many scriptures that refute that misunderstanding and devise elaborate explanation of certain scriptures and add other but cannot infuse the scriptures that many many times show that deception has serious consequences.
Not just losing a little of this and little of that, but losing of it all.

The ten virgins 5 where wises 5 where foolish.

In the end God knows I suppose.

Is once saved always saved and primary doctrine?

Once saved always saved is just not so fundamental as some would like it to be, it take a lot of explaining to wash away certain scripture.