Mixmaster is a Decepticon who transforms between his robot mode and his cement mixer mode.  He is one of the six Constructicons (along with Bonecrusher, Hook, Long Haul, Scavenger and Scrapper) who combine to form Devastator, Mixmaster transforming into the left leg of the giant robot.

With the function of Materials Fabrication he uses many different items, even functioning robots, to create new materials inside his mixing drum.  His procedure includes using acids and bonding agents to break the items down in order to be made into something new (according to his Tech Spec).

The Constructicons were released individually in 1985.  They were also available together in the Devastator gift set during the same year.