Perro de Presa Canario
Also known as the Canary Mastiff, the Perro de Presa Canario is a tough breed. Sometimes these dogs are trained as fighters and they can be aggressive if not trained properly.
Although these dogs can be dangerous to other dogs, they aren’t so bad with humans. They have been known to attack other dogs in the past and sometimes kill them. This breed probably isn’t one you will want to take home if you have other animals there. They also need to be kept away from potential targets for their aggression or prey.