Chimerical

Adjective

1. Of or pertaining to a chimera.
2. Being a figment of the imagination; fantastic (in the archaic sense).

   "a chimerical goal"

3. Inherently fantastic; wildly fanciful.
4. Resulting from the expression of two or more genes that originally coded for separate proteins.
5. Impossible to physically produce due to having an impossibly-high saturation or luminosity, but viewable by overlaying an afterimage and a suitably-colored physical image.