It is important to consider that "angel" means messenger - before attempting to depict the totality of Satan's deception on many. Satan is considered a "messenger" of light. Messengers always have a message, and engraved within the message of "light" is the edification of self, self freedoms, self-indulgences, self-power, self-centeredness, self-sufficiency, self-government, self-purpose, self-forgiveness, even to the point where you empower yourself to even forgive "God" - etc. Self-pride is rooted in the very center of this doctrine, and you could see it clearly in society, in cultures, in businesses, and even if looked closely, within "oneself". This message of "light" encourages your deepest emotions, "if you feel good" it must be right. It is a very subtle doctrine which sometimes wakes us up in the early hours of the day, and asks "so what can I do, to make myself feel good today" rather than "what can I do to obey God today". It becomes a doctrine of "me" rather than of Jesus Christ and dying to self.
The message of Satan never directs you to "the light of the World" (Jesus Christ) but emphasizes greatly the empowerment of self, and its freedoms and government. John said it clearly, "He (Christ) must increase, and "I MUST" decrease. This is the truth!