He deceives them day to day, so they deceive themselves and many restraining them where he wants them (John 10:10/2Cor.4:4). But not as much as how he does to GOD's people, even ones who are more aware of him. The scripture depict, he does even more than that, with the inhabitants of the earth and sea.
Revelation 12:
12. Therefore rejoice, ye Heavens, and ye that dwell in them. Woe to the inhabiters of the earth and of the sea! for the devil is come down unto you unto you, having great wrath, because he knoweth that he hath but a short time.
Brethren, how the scripture is truth, are we not witnessing the situation under the sky, the earth and sea until to date? Aren't things within these realm are just spiraling from worse to worse and in disorder? Isn't it far from what good and in order GOD created in the beginning for the inhabitants?
Now, about demons;
Mark 5:
8. For He said unto him, "Come out of the man, thou unclean spirit."
9. And He asked him, "What is thy name?" And he answered, saying, My name is Legion: for we are many.
12. And all the devils besought Him, saying, Send us into the swine, that we may enter into them.
13. And forthwith Jesus gave them leave. And the unclean spirits went out, and entered into the swine: .................
i perceive by the wisdom given me, legion is a division of 3,000 - 6,000 unclean spirits in unity to be know as, demon. And even in the realm of darkness there's unity, even the worldly people who love their own (John 15:19).
Shalom in the name of Jesus Christ