Ha-Ha

 was a member of the punishment platoon on Hedgewick's World of Wonders. He yelled at an attacking Cyberman that he wasn't afraid of it to get attention, and Clara shot it down with an anti-Cyberman weapon. When two partially converted humans began approaching Clara, she threatened to shoot, but Ha-Ha explained that the hand pulses could deactivate them just fine. He was almost upgraded by the Cybermen, but the Eleventh Doctor, whose mind was partially taken over by Mr Clever to pull in the resources to decide a chess move against Clever. (TV: Nightmare in Silver)