Also referred to by his God-given name of Heylel , Isaiah ch 14 (Lucifer is a Latin acronym) , he was the highest angel in rebellion to God to not receive direct punishment, apart from having God Life removed, which explains the blood sacrifice elements, child abuse/sacrifice etc, for the Life is in the Blood.. After his attempts to be like God failed, he was cast down from Heaven as a fallen angel. His current dominions are hell, the aerial atmosphere as prince of the power of the air, and the corrupt world system.
Satan is the most evil being to ever exist. His rebellious nature against God gives him pride in taking as many souls with him to damnation as possible. In short, he knows he's going down, so he wants to take down as many people with him as he can.