He hates and fears Christ. As Christ said, if His enemies call Him Beezlebul, then how much more will they hold His followers in contempt. I’ve noticed that in the world the leaders of even destructive or evil movements are given a certain respect, whereas their followers are often treated like so much dirt or cannon fodder. Examples are Hitler, Stalin, Pol Pot, Kim Jong II, Bin Laden, Mussolini, Tojo, Saddam Hussein (think of all the trouble the Americans went to to give him a public trial, whilst killing thousands of his troops in bombing raids) and so on.
Therefore Satan hates all Christians, and will if he can try to load contempt on them. As far as that goes he hates the human race, even those who serve him. But they are not a threat to him. He will even lend them his power if it suits him eg. the Third Reich (that’s where it got it’s power and brilliance from). They pay for it later though. Yet one wonders what holds Hell and the demonic forces together, because it sure isn’t love.
However I think he is very concerned that Catholic truth should be suppressed, and that Christ’s call for Christian unity should be suppressed. Hence the office of the Pope in particular is singled out for attack, not only by non-Christian enemies, but also by those who follow Christ, and who fail or refuse to see the implications of Christ’s promise to Peter. As a former Protestant, rest assured the toughest battle on the road to reunification will center on the Chair of Peter.
As for individual Christians, Satan’s efforts are to some extent tailored to hit hardest those whom he thinks are the greatest and most effective threat. And that will not depend on their denomination. He is most detemined to destroy those who he perceives as dangerous to him.