7. Presa Canario
The presa Canario is a mastiff-type dog that usually makes its way to the list of banned breeds thanks to a period in its history where it was used in dogfights. The breed was originally bred to protect farms and work with livestock, and they are very protective of their families. Well-trained presa Canarios make loving companion animals, but it takes work and consistency. Poorly trained or neglected presas, on the other hand, can be a danger to humans and dogs.