Grellig

Grelligs are a non-sapient species of swarming, voracious rodent-like beings originally from the planet Ondrocka; located in the mysterious "Divergent Universe" visited by the Eighth Doctor and Charley Pollard. Thanks to the spacefaring ventures of the Ondrockans, the Grelligs have also been spread to other worlds as invasive species.

Appearances

 * Big Finish Doctor Who audio stories, "The Twilight Kingdom" (2004)