None.
Very mild scenes showing young Hans bullying poor little girl Alice.
One scene shows people throwing tomatoes at a man, while an another scene much later shows people doing the same thing to two men.
Three cats chase rats. A fighting takes place off-screen, but it is revealed the rats have won over the cats.
Several unseen kids throw smoke bombs at a horde of rats.
Some people threaten to hang the town clerk.
Young Peter uses his wooden sword against a small horde of rats, and mentions about chopping off heads and tails.
Peter falls down the stairs and hurts his left foot.
Mild words are uttered throughout. Such as "fools", "silly cats", "stupid" and "poppycock".
None.
The rat suddenly running very close to the screen in the intro may startle some children.
People with fear of rats may not like this film very much, as the majority of the first half of the film centers around the town Hamlin being plagued by a horde of rats. But it's all animated.
There is nothing intense or frightening in the film itself, as this cartoon film is suitable for children.