Alternate versions

The version of the film released to theaters omits numerous fully animated scenes that include shots of graphic violence as Taran fights his way out of the castle and shots of Eilonwy sporting ripped garments as she's hanging for her life with Taran and Fflewddur. The most well-known deleted scene, due to a clumsy jump that it left in the film's soundtrack and a cel of the infamous scene appearing online, is that of a man being mauled by one of the Cauldron-born.

In the Latin Spanish dubbing some characters' names where adapted for the dubbing. Taran was "Taron", Eilonwy was "Elena", Fflewddur Fflam was "Fausto", King Eidilleg was "Rey Enrique" and The Horned King was "El Rey del Mal" (in English "The King of Evil").

Appalled by the film's darkness and graphic nature, and also concerned with its long length, Jeffrey Katzenberg requested that the film's release be delayed from its scheduled Christmas 1984 release to July 1985 so that the whole film could be reworked. The Black Cauldron (1985) was ultimately cut by twelve to fifteen minutes, all of which were fully animated and scored. As a result, some existing scenes were rewritten, reanimated, and reedited for continuity. Many of the cut scenes involved the undead "Cauldron Born", who are used as the Horned King's army in the final act of the film. While most of the scenes were seamlessly removed from the film, one particular cut involving a Cauldron Born warrior killing a person by decapitating his neck and another one killing another person by decapitating his torso created a rather recognizable lapse because the removal of the scene clumsily creates a jump in the film's soundtrack. Other deleted scenes include: many scenes of graphic violence such as the ones where Taran fights his way out of The Horned King's palace with the magic sword Dyrnwyn; shots of Princess Eilonwy wearing ripped garments, as she's hanging for her life with Taran and Fflewddur Fflam; whole sequences involving the world of the Fairfolk; scenes of the Horned King with a flowing cloak; one scene featuring one of the King's henchmen being mauled by one of the Cauldron Born warriors, which causes him to form horrifically detailed lacerations and boils, before he rots away to become one of the Cauldron Born warriors himself (a couple of animated cels of that particular scene can actually now be found on the Internet); and a more action-oriented, dramatic, and intense climatic fight scene between Taran and the Horned King before the latter is sucked into the Cauldron.