Wooden Cyberman

The wooden Cyberman was a variety of Cyberman created out of wood during the Siege of Trenzalore. Its purpose was to enter Christmas undetected, as wood made it low-tech, preventing it from triggering the Papal Mainframe's alarm system as it passed through the force field. It was tricked into taking its own life by the Eleventh Doctor as it did not know the sonic screwdriver did not work on wood. This Cyberman shot flames with its gun (similar to a flamethrower) and used the phrase "incinerate", unlike other Cybermen, who used "delete". It also had a light tinted yellow speech indicator as well as a yellow chest piece, both of which were blue for all other Cybermen of the same design. (TV: The Time of the Doctor)

Behind the Scenes
The Wooden Cyberman is featured in Wooden Acting, a WeLoveTITANS backup comic strip. However, this is not considered in-universe and is relocated at a different page.