Well then, please demonstrate evidence for this Satan anywhere in the universe prior to “his” involvement with human beings.
Satan the serpent had to have gotten that knowledge of good and evil he whispered into Eve's ear before he involved her in his seduction. Moses pens in Genesis 1:2 of the King James Version And the earth 'became' without form and void: and darkness was upon the face of the deep. ....
What is the evidence you require as acceptable for demonstration? There are all manner of dino fossils that demonstrates an age before flesh man was put upon this earth. The earth is pocked full of marks that demonstrate some kind of cataclysmic action took place eons ago.
I can't point to "his" activity in the universe, but then mankind's knowledge of the universe (and mine) is quite limited. For example, try to envision God activities outside His involvement with man?
Our perspective is limited to our experience...and our experience, with a few exceptions, is limited to this planet.
What I can do is tell you that Scripture is full of circumstantial evidence and direct discussion of his existence. Furthermore, there are authoritative figures outside the religious community who have experience with such an entity.
For example, Scott Peck's book "People of the Lie" provides an interesting chapter on demonic possession and the involvement of the psychiatric profession in exorcisms.
BTW, it is not my place to try to convince you one way or another as to Satan's existence or lack thereof. It is a spiritual matter and that requires a personal search for proof or evidence of a different kind. Also, as is the case with God, whether you believe in his (Satan's) existence or not is unrelated to whether or not he exists.