All things being equal, Satan, also known as the adversary or the great enemy of goodness, is delighted in all those that do not believe in God, or believe in a God that has flaws, faults, and limits, or believe in a God which fundamentally fails to recognize God as being omniscience, omnipotence and forever, eternal. Basically, the more unbelief in God and the more unbelief in the goodness of God held by mankind, the more delighted that Satan is. So too, Satan does not want human minds to be conflicted as to what they really are, which are souls created by God, but rather wants them to see themselves instead as being limited to just this material experience, and ideally without knowledge or belief that they have a spirit or soul, and therefore to believe that this material life is therefore their only existence.
In point of fact, Satan knows all about God, recognizes the unconquerable power of God, but knows very well that God is patient, loving, and kind, in which, even misguided souls such as Satan have their place; for without darkness to contrast with Light, or evil to contend with good, then the drama that tests and challenges mankind on earth, would basically have no real substance. After all, no test can really be conducted against the character of a given individual, unless there are real choices and real consequences of that test, so Satan plays the part of representing that there are indeed other options other than just surrendering oneself to God.
Yet, it is important to note that the battles here on earth most definitely have consequences, of which, those consequences are ultimately paid by those individuals that fail their tests, for each individual is ultimately responsible for their own volition so exercised. This means, for everybody here on earth, that those that are ignorant of the truth, suffer for it; and those that deliberately walk away from truth, also suffer for it; whereas all those that know the truth but deliberately misled others, suffer most of all, for themselves as well as for having done their neighbor wrong.
In all of this deception, Satan delights, for Satan holds absolutely not a whit of power in Truth, for Truth is the ultimate power, which is, unconquerable. This means, that Satan must operate in the shadows, in the doubts, in the character flaws and mistakes, that humans are so prone to make, and by working on those human foibles, Satan can have loads of fun at the expense of those so tricked or fooled. Of even more satisfaction to Satan, though, are all those that after receiving a little taste of doing wrong, or doing evil, or lying, or deception, become enraptured by it, and therefore on their own, with nary any prodding by Satan, perform acts on an even bolder scale, of disruption, hate, and intolerance, making for a more miserable life for so many.
Satan wants as many as possible to forget that they are actually souls created by God, seeing themselves instead as just material beings, subject to material laws, of ill health, lack, finiteness, and death; knowing that those that live lives without good purpose and meaning, are functionally lost, and susceptible to all sorts of wicked enticements which amuses Satan to no end, at the expense of all those, that have been deceived by that great deceiver.