I forgot the name of the film, which involves a red light glowing dinosaur, or something similar to Godzilla.
In the story, people are trying to stop it and using earthwork to trap it with the equipment they have. The hero joins some people around there, then makes a sword to attack.
The thing comes at night. There is a scene where the hero throws a stick torch into a dark area where the creature was hiding, and then red light glows on its body.