5: BULLMASTIFF

Bullmastiffs are astonishingly massive animals that are apparently, unbelievably quiet. In their early years, these dogs were bred to watch over livestock. Due to their imposing size, it was enough to scare off any kind of danger without actually attacking. Despite their huge size, these days, Bullmastiffs are known to make good family pets, even getting along with the smallest of children without fear of harming them.