Scar has just missed the presentation of Simba, Mufasa's son who is to be the next king.
Scar turns as if to leave and Mufasa stops him by saying "Don't turn your back on me Scar." This is a warning.
Both are the story of a young man who is torn apart by the early demise of his father.
An uncle takes over the thrown that should rightly belong to the young prince, and both of the tragic heroes overcome their own flaws and uncertainties to take back their thrones for the benefit of their countries.
It can therefore be accepted that he probably let it be known to Hamlet Sr. Scar shows how it is in the nature of the truly evil to have their victims know they are going to die.
If the victim knows(if only in the mind of the murderer)and does nothing, then that makes them all the more useless, and deserving of death.
Scar shoots back "No, perhaps you shouldn't turn your back on me! Because the king is never introduced in Hamlet, the audience is left to wonder whether the king had any notice that his brother wanted him dead. Shortly after Hamlet visits his mother and kills Polonius, there is a meeting between him and Claudius.
When Hamlet is told he is being sent to England, he affirms that this is a good idea, and the king replies "So is it, if thou knew'st our purposes."(IV, iv, 47) The king is letting it be known that he has it in for Hamlet.
He leaves the pride and wanders into the forest, wanting to die.
Timone and Pumbaa rescue him by carrying him into the shade when he faints from the heat of the sun and his only desire is to keep going until he dies. Like Hamlet, Simba tends to need to be on his own a lot to reflect.