Pippin talks to a "living head" he finds on the battlefield.
The talking head of the decapitated Visigoth was created by filmmaker Christian Schaefer.   It had bloody tendrils hanging from it, as well as the bony, bloody neck stub coming out of his shoulders.  The head was animated with the mouth and the eyebrows moving, to give it a lot of expression.  This scene, and the scene in Act II brought the house down every night.