Mar'tuth
From Tardis Wiki, the free Doctor Who reference
Mar'tuth was a humanoid alien that seemed to make the air around it pixelate and rip. It could destroy things, such as a spaceship, by contact of its "glitches".
Mar'tuth tried to hunt down Maxie, but was ultimately defeated when Maxie and Giles lured it to a branch of Homestyle, where they defeated it by using mirrors to deflect its glitches back onto itself, causing it to turn to blocky dust. (PROSE: She Came From Another World!)