Appearance/discussion of Necropolis units.

I don't agree with you, take any vampire movie, they have their own world, their own clan and they are far from being stupid creatures who only need blood.....

It all depends on WHAT kind of vampires. After all, there are also ghoul-like creatures (upyrs), sort of poorly put-together vampires who really do only need blood and meat. Otherwise, I agree with you.
As for the sword, it doesn't hinder them at all, as has already been mentioned here. Let me tell you about certain vampires called Nosferatu, who don't need to "sink" their teeth into a victim's throat at all. It is enough to simply slightly cut the client and, using dark vampiric magic, suck the blood directly from the wound from a distance, which, by the way, is depicted quite vividly in the game BloodOmen2. After everything I've said here, attention, question: Why do vampires in 5 need swords?;)