As a foil to Brutus, Marc Antony shows his loyalty differently. While Brutus respects Caesar:"yet I love him well (I,ii,82), he slays Caesar out of loyalty to the state and its welfare:"Not that I loved Caesar less, but that I loved Rome more (III,ii,22), Antony weeps, "Thou art the ruins of the noblest man/That ever lived in the tide of times" (III,i,256-257). Because he is alone critics argue that this speech is evidence of Antony's genuine love and loyalty to Caesar. He wants Caesar alive, not dead for political reasons.
In order to avenge the death of Caesar, Antony employs ironyin his oration--"So are they all, all honorable men"(III,ii,84)--as well as emotional pauses to arouse the people to turn against the conspirators.
Later in the play, Antony again manipulates people. In his love for Caesar and loyal promise to avenge him
"A curse shall light upon the limbs of men:/Domestic fury and fierce civil strife/Shall cumber all the parts of Italy(III.i.262-264)
Antony is willing to sacrifice the life of his own nephew. He agrees to trade his nephew's life for that of Lepidus with whom he has formed a political alliance along with Octavius. However, when Lepidus leaves, Antony tells Octavius,"This is a slight unmeritable man,/Meet to be sent on errands" (IV,i,12-13).
Still acknowleging loyalty, Antony recognizes it in the dead Brutus:"This was the noblest Roman of all.(V,v,68)