Macbeth is presented as a multi-layered figure, a tragic character whose heroism erodes as ambition and fear overtake any noble qualities he once possessed. His fall is great, from the good impression he in his first appearance to his final moments as a frenzied tyrant taking a futile last stand.
The audience's first impression of Macbeth is colored with heroic valor. Before he even appears onstage, a sergeant sings his praises:
For brave Macbeth—well he deserves that name—
Disdaining fortune, with his brandish'd steel,
Which smoked with bloody execution,
Like valour's minion carved out his passage
Till he faced the slave;
Which ne'er shook hands, nor bade farewell to him,
Till he unseam'd him from the nave to the chaps,
And fix'd his head upon our battlements.
From the very beginning, Macbeth is linked to violence, however, this is violence sanctified by both his patriotic goals and its place on the battlefield. Ironically, this noble battle foreshadows Macbeth's own death at the hands of Macduff once he becomes the tyrannical threat to Scotland's peace. Still, here he is praised as "valiant" and "worthy" by King Duncan and presented as an ideal warrior: loyal, brave, and decisive in combat.
This noble image of Macbeth begins to fade almost as soon as he makes an appearance onstage. When confronted with the witches' prophecies, Macbeth is intrigued rather than repulsed, revealing his hidden ambition for power. However, this intrigue is complicated by Macbeth's strong sense of doubt: he comprehends the psychological weight of committing a murder, which is wholly distinct from what he does on the battlefield. Once Lady Macbeth learns of the prophecy and starts wearing away Macbeth's moral resistance, Macbeth appears more indecisive and far less noble, easily moved to regicide by his lust for power and anxiety about his own manhood.
While Macbeth is often considered a tragic hero, like Hamlet or Othello, he is far more villainous than either, ordering the assassinations of those who pose the least bit of threat to his power, including innocents and his own former friends. As king, he loses the qualities that once made him a great warrior, which only reappear right before he dies in combat at the end. Ultimately, Macbeth is presented as a heroic figure whose succumbing to temptation turns him into a tyrant.