What is the dramatic contribution of character of Iago in the play "Othello"

Throughout William Shakespeare's play "Othello" ,we learn a lot about the dramatic contribution of character of Iago , his insatiable desire for revenge, and constant deception of the entire cast. we are aware of this deceit through the dramatic irony employed throughout the play in the form of soliloquies and the ruse of the 'honest Iago'. He is a ruthless sociopath. Shakespeare employs the format of the tragedy to his play. No other character can even …

…the dramatic contribution of the character Iago is decisive which made the protagonists an interesting and fascinating study in evil. A practised liar and cruel political opportunist, Iago delights in his own manipulative skills and relishes turning other's 'virtue into pitch.' By the end of the play , the characterization of Iago by the Shakespeare in the play leaves the audience with much food for thought and the discussed characteristics firmly entrenched on their minds.