I would argue that everything that has been made was made during the first six days of Creation Week; at the end of which, God pronounced everything “good”–including the archangel Lucifer, who must have been created early in the week, since apparently the angels were immediately put to work helping to finish getting everything ready (Job 38:4-11); and man was created on the sixth day.
Angels were to serve man (Hebrews 1:14); and perhaps glorious, immortal Lucifer thought that was beneath his dignity?
I would argue that the Tree of the Knowledge of Good and Evil set a parameter, a relationship boundary. In essence, it was an “Exit” sign out of the Garden, although not out of the classroom.
The Tree itself was not evil; and the fruit of that Tree was not anything supernatural; rather, the choice to eat it made an opening through the divine hedge of protection around Creation for the legalistic devil to exploit–allowing him to come in as the god of this age (2 Cor. 4:4), pervert nature, and bring in death and destruction. And we recall that death is an enemy of God, which will one day come to an end (1 Cor. 15:56); and that the power of death is the devil’s, not God’s (Hebrews 2:14).
[And of course, the idea that death came into nature through Adam and Eve’s sin (1 Cor. 15:21, Rom. 5:12) controverts the theory of Darwinian macroevolution, where death is required as the central mechanism for the rise of “humanoids.” I have argued elsewhere that the sedimentation of the fossil record is evidence of the Flood of Noah, revealing how great the corruption of nature had become. And that God did not send the Flood; rather, Satan did.]
We don’t know how much time elapsed between the fall of Lucifer, and his entrance into the snake; presumably not too much, since Adam and Eve still had no children when he tempted Eve.
The essence of the Satanic lie was: “Eat this fruit and you will know God as He truly is, as BOTH good and evil. And you will know yourself the same way, as BOTH good and evil.”