The Bullmastiff originally the Game Keepers, nightwatchman makes an amazing pet. Nicole and her boy Jax show us how beautiful Living With a Bullmastiff can be. If you have considered a Bullmastiff as a house dog, be sure that there are rules and regulations that will guide your giant dog for proper behavior. Training a Bullmastiff is a must. The Bullmastiff is a large breed, intelligent and strong willed. To keep this dog happy and your home in one piece you will have to be a involved and mindful dog owner. Jax is an AKC Grand Champion and undoubtedly the kind of Bullmastiff a new owner should be looking for.