Deception

           Oh thou art foul, thy 'honest' Iago."the food that to him now is as luscious as locusts, shall be to him shortly as bitter as coloquintida." I was being decieved from the beginning, this I had figured out, but you quickly rused me into doing your bidding once more. This had cost me my life, and my dignity. I was below the pure Desdemona, but you convinced me that i could raise myself up to her on the chain, and move Othello out of the way. Your lies and deception proved to be truly fatal.

Literary Devices
Metaphor: Iago had compared Desdemona to food that he desired, and that Iago would convince Othello that she was not to be. He used this to create the thought that Roderigo would become desirable once Othello was no longer with Desdemona.