Cassowary
The cassowary, listed in the Guinness Book of Records as “the most dangerous bird in the world,” is generally docile but shows no mercy to those it perceives as enemies. A direct kick from its powerful legs can easily break human bones. If it truly exerts itself, it could even be lethal. However, there have only been two reported deaths caused by cassowaries to date.
One incident involved a 16-year-old boy who attempted to beat a cassowary to death and was killed in retaliation. The other case involved a 75-year-old man who was attacked by his pet cassowary. In this instance, the man was apparently attacked when he fell, but in both cases, it seems the cassowary reacted out of surprise. This means that, generally, you won’t be suddenly attacked as long as you don’t upset a cassowary.