Who were Macbeth's chief opponents and what has happened to each?

Answer 1

At the start of the play, before meeting the witches, Macbeth is still loyal to Duncan. The forces of Norway and the rebel Macdonwald (whom he kills in battle) could be considered his adversaries at this point in the play.

After he meets the witches and begins to entertain thoughts of regicide, anyone who stands between him and power becomes his adversary (Duncan, Malcolm, Banquo, Macduff...)

One could probably make an argument as to why Lady Macbeth might be considered Macbeth's adversary as well.

Answer 2

Macbeth's chief opponents were Macduff, Malcolm, and the English forces led by Siward. Macbeth was ultimately defeated in battle by Macduff, who was able to avenge the murder of his family by killing Macbeth. Malcolm then became the new king of Scotland.

Answer 3

Eventually lots including Malcolm, Donalbain, Fleance and particularly Macduff.