Gu was a legendary creature that looked like a worm but was slimmer than a worm. There were stripes on its body that could poison people's hearts. The poison of the Gu was very strong and could cause a person to fall into madness, coma, or even death. In some novels and movies, voodoo was described as a mysterious power that could control human thoughts and actions, with the ability to control and manipulate. However, the question of whether Gu really existed had not been confirmed by the scientific community, so it was impossible to give a definite answer.