Violence against robots is different than against humans, but puzzlehead looks just like human, so in this case, scenes of violence done by, or done against Puzzlehead could be viewed as violence done by, or against real humans.
Puzzlehead gets mugged and shot in the chest in the first half of the movie.
A man is harassing and molesting Julia, the shopkeeper.
Puzzlehead breaks the arm of the gun wielding men robbing the store.
Walter forces Julia to have sex with him. Light violence. Explicit scenes are not shown in the movie.
Julia tries to commit suicide with a barber blade in a bath tub. Puzzlehead bangs his head in the sink. Warning: blood and self-inflicted violence.
When Puzzlehead is walking on the street, three men are fighting, beating each other in the background.
Puzzlehead tries to kill Walter by burying him alive.
Puzzlehead shoves Walter off the top of a building. Walter falls to his death.