Complete Monster: Every millennium, Satan escapes from Hell in a bid to destroy the world by fathering The Antichrist and opening a portal to his own domain. In his opening scene, he possesses a New York businessman; makes out with his friend's wife in front of him, then blows up the crowded restaurant they're in. He later ditches the host when the body is close to death. He happily murders his minions and random strangers to blow off steam; crucifies a priest to a ceiling and later massacres a roomful of them; burns Jericho's best friend/partner Bobby Chicago alive after he refuses to kill his friend; tries to rape Christine, the girl who was chosen to carry his offspring; and forces Jericho to relive the murder of his wife and daughter after he refuses to help the Devil in his plans.
Evil Is Sexy: The real threat of Satan is that Christine finds him so damn sexy. Hilariously, this extended to the production. When Gabriel Byrne as the Devil spontaneously kisses a woman in a restaurant, female extras were basically fighting over the part.
Genius Bonus: One of the first things that Satan does upon arriving on Earth is to have a threesome with Dr. Abel's wife and daughter. This is something the Bible specifically mentions as a big no-no, so it's understandably something that the Devil would delight in doing.