Early in the play, we see that Macbeth, though not without a sense of honor and loyalty, allows his ambitions to supersede and eventually drive these virtues from his being, so to speak. After meeting the witches, he is very quickly aware that their prophecy that he will be king has awakened chilling emotions. He refers to his "black and deep desires," which he resolves not to reveal to his fellow thanes. Once he has murdered Duncan, a deed he recognizes as evil on every level--he was his cousin, his liege, and his guest--he experiences considerable guilt, but does not allow it to stop him from carrying out even more horrific deeds. He has his friend and comrade Banquo murdered, he sends assassins to kill Macduff's family, and he presides over a bloody reign as king, one which is described by several of the other characters in the play as tyranny. By the time Malcolm's forces advance on Dunsinane, he is a murderous monster devoid of any redeeming characteristics. Having usurped the throne (an act Shakespeare portrays as a violation of nature itself) he unleashes havoc on Scotland.