Rejoice! I Am Ultimo Thy Deliverer - S1-E2
Revealing mistake: When Mandarin and Modok are watching Iron Man and War Machine fly circles around Ultimo, the monitor they are watching is shaking, likely indicating a composite shot.
Life Lessons - S1-E4
Revealing mistake: When Danziger and True are pursuing Gaal, they drive up next to Gaal and his horse. In several shots it's obvious it isn't Danziger driving, but a stunt double. (00:47:10)