Mecha Head is an enemy in Final Fantasy V.
Many of them can be found crawling in the Pyramid of Moore. Its attacks include Surge Beam, Reverse Polarity, Mustard Bomb and two Blue Magic spells, Missile and Flamethrower. It also has a hidden Blue Magic spell ??? that can be learned by Controlling it. A Thundaga charged Spellblade will inflict Instant Death (ignores immunity to Death).
In the Advance remake of the game, Mecha Heads can also be encountered in the Hall of Watchmen and the Tomb of Memory areas of the Sealed Temple.