Originally developed in Detroit's Metro area, the early Panja Mastiff was a result of crossing Pit Bull Terriers, Rottweilers and Bandogs, although other breeds like the Bullmastiff, American Bulldog, Cane Corso, Doberman and the Presa Canario have reportedly been involved as well. The present-day Panja is more uniform in type and has a fairly specific "recipe" for its creation. This dog shouldn't be confused with the popular bandog variety known as the "warlock", which is simply a 1st generation APBT/Rottweiler cross, whereas the Panja can be achieved either by crossing two "warlocks" together or through planned matings of "full" Panja Mastiffs with Rottweilers.
Initially associated mostly with drug dealers and gangsters, the Detroit Rock Dog was often employed as a guardian of their properties and as a pit-fighter, but it was its common use as a "bodyguard" which earned the Panja its reputation as a personal protection breed. Even though it has unpleasant beginnings and somewhat dark roots, this is an increasingly popular breed today, thanks to the efforts of some responsible breeders that are producing dogs of sound temperament and agreeable personality. However, potential owners should research the breeders and try to avoid bloodlines known for overly vicious and unstable dogs, as well as poorly bred 1st generation crosses, which are still commonly encountered in the population to this day.
The American Panja Mastiff takes its guarding duties very seriously and can be fairly dog-aggressive, which is why it requires proper handling and socialization. However, when raised and handled properly, it can be a well-behaved and reliable companion. Athletic and agile, this wide-chested and muscular breed is affectionate and gentle with children, making a good family dog. There is still a variety of types to be found, depending on which breed's influence is stronger in a specific bloodline, but most Panja Mastiffs are strong-boned, broad-headed and easy-moving Molossers. The ears can be cropped or left in their natural state. The tail is usually docked, but many unaltered specimens are commonly encountered.
The coat is flat and short, but quite dense and thick, accepted in a variety of colourings, from solid fawn, red and black shades to various bicolours, such as white-based particoloured and darker dogs with small white markings, as well as black-n-tan and tricoloured specimens.
The average height is around 25 inches, although smaller, as well as much taller dogs exist.