Selyoid

The Selyoids were beings of pure light. They called themselves the Children, with Leonard de Sande dubbing them "Selyoids".

Selyoids were originally beings of light, but climate change caused their scientists to devise a corporeal form. Their corporeal form was a primordial soup capable of travelling through space on an asteroid.

On their own planet, the Selyoids lived purely to express their creativity, as a race of artists. Their scientists were outcasts.

The Selyoids once invaded Los Angeles and somehow changed movies, including The Time Machine. The Second Doctor, Ben and Polly stopped them. (PROSE: Dying in the Sun, Synthespians™)

Behind the scenes

 * The name of the Selyoid obviously derives from, a chemical used at one time in the production of.