The Cheshire Cat

The "fabled" Cheshire Cat was a being native to Wonderland, documented accordingly within Lewis Carroll's Alice in Wonderland. (AUDIO: Iris Wildthyme and the Land of Wonder)

Biography
The Cheshire Cat was known for vanishing "a piece at a time". After talking with Ace, Legion vanished in a similar fashion. (PROSE: Lucifer Rising)

Legacy
After the Eighth Doctor was infused with anti-time and had taken the persona of Zagreus, his TARDIS worked to keep the Zagreus persona subsumed by holding him near a concentration of Zero Energy. The TARDIS reconfigured one of its rooms into a forest with a replica of the Cheshire Cat, known as simply "the Cat", perched on a tree branch. (AUDIO: Zagreus)

The Tenth Doctor was described as having a grin like the Cheshire Cat. (AUDIO: The Shattered Hourglass)

Behind the scenes

 * The Cheshire Cat was voiced by Stephen Fry in the 2010 film version of Alice in Wonderland.