Mezmerella was created in late 2009 for the Boom! Studios Incredibles series I was co-writing with Mark Waid. Although he did not work on the Incredibles, Eric Jones stepped in and designed the character, which in turn was rendered by Marcio Takara (I think it's his art used here) and Ramanda Karmarga (who I believe drew the Underminer in the above image). The colors scheme for the character was selected by editor Aaron Sparrow and the name (originally Hypnotica) was the idea of my wife, Belinda Adams.
So alot of credit goes to alot of people for the character. It's pretty exciting seeing something I conceived of being a part of a Disney attraction of any kind. Even more fun to see young children interact with the inanimate character by throwing things at it.
My favorite quote from the video: "Mezmerella gets kneecapped!"
Here the full video:
Special thanks goes to FigmentJedi from the Pixar Planet forum for pointing this out.