Standing in the shadow
Scar is the perfect villain: machiavellian, arrogant, condescending of his inferiors (although, to be fair, the hyenas are pretty pathetic), and full of his wish for revenge. So it’s no surprise that, in his big musical number, he works hard to underline his evilness.
But the imagery that Disney uses to reinforce this also helps to give the impression that Scar is an irredeemable bad guy. During the scene when he is standing on the edge of a precipice and looking down at his followers, the shadow behind him is actually an eagle, the symbol of the Nazi 3rd Reich. See? Bad guy.