None.

In classic cartoon tradition, there is some comedic cartoon violence, and no one dies. (edit: Actually Daffy dies at the end, he performs an act he can only do once (a suicidal magic act) and he turns into a ghost.)

One use of "hell" in a literal term.

A few of the gangsters are seen with cigarettes in their mouth every time they appear on screen.

The first act, with the Hellish picture might be frightening for little children. But for the most part it's mostly not meant to be taken seriously.

No scenes in this film are considered frightening. This film is strictly comedy.