Mute (A Stitch in Time)

From Tardis Wiki, the free Doctor Who reference

In an alternate timeline version of London in the year 5000, mutes were vicious mutated humans who rode six-legged camels.

A single Mute rider chased the Third Doctor when he arrived in the alternate Earth, but was knocked unconscious by a metal piece thrown by Brod. (COMIC: A Stitch in Time)