Before the film was released, several scenes considered too "graphic" where cropped out of the film. One particular cut involving a Cauldron Born killing a person by slicing his neck and torso created a recognizable lapse due to the fact that the removal of the scene creates a jump in the film's soundtrack.
As the Horned King prepares to activate the Cauldron, he first pulls away the tarp over the cart of dead warriors. The next shot shows the Horned King already holding up one of the corpses over his head.
In the swamps of Morva, Fflewddur Fflam is talking to Doli, who is sitting on his hat. On the first full shot of Fflewddur, Doli is not visible, although Fflewddur is clearly looking up at him. The next shot is a close-up of the hat, with Doli on it, then back to a full shot without Doli.
When Fflewddur Fflam is locked up in the dungeon, the number of strings on his harp changes between shots from 5 strings in the wide shots and 8 strings in the close up shots as they start to snap off. Then later on, the harp is back to 5 strings straightened out.