Iron Knight was Iron Man altered by Morgan Le Fay's reality distortion wave. The wave caused the time period to be altered to a medieval setting altering the Avengers clothing, speech patterns and thought processes. All of the Avengers involved believed themselves to be a part of the Queen’s elite guard known as the Queen’s Vengeance.
Powers and Abilities
Tony Stark has no powers of his own but they are derived from his Iron Man Armor.