The Brainiac (1962)

Starring Abel Salazar, Ariadna Welter, David Silva, German Robles, Luis Aragon
Directed by Chano Urueta
(actor & director credits courtesy IMDB.com)

In the 17th century, a baron with supernatural powers is condemned to death, but makes good on his promise to return 300 years later to murder his sentencers' descendants.

Urueta and his cast and crew deliver one of the wackiest Mexican horror films around, primarily due to the bizarre looking monster Salazar transforms into, a sharp nosed disheveled creature with a pulsating head, fangs, and a forked tongue used to extract its victims' brains.  There's not much to the plot besides that, and there's several elements in the screenplay that don't make sense, although there's some amusing scenes where Salazar digs into the brains he's stolen as if eating a dish of ice cream.  Fans of Mexican horror should enjoy the loony goings-on, and a dark music score by Gustavo Cesar Carrion effectively establishes the macabre tone.