Pitting animals against each other remains a hot topic today. Blood sports, as they are called, are illegal in many countries, although they remain legal in some. A few centuries back, they were perfectly legal and were a pastime. Humans even bred animals specifically for blood sports.

Some of those purpose‑bred creatures vanished once the sports were outlawed, while others survived in pockets of tradition. Below we count down ten animals that were deliberately engineered for combat, cruelty, and spectacle.

Animals Specifically Bred for Blood Sports

10 Cordoba Fighting Dog

The Cordoba Fighting Dog is an extinct breed that was purpose‑bred for dog fighting in Córdoba, Argentina. Its lineage is thought to be a mash‑up of Spanish fighting mastiffs, bulldogs, and Bull Terriers, giving it a lethal mix of agility and aggression. The dogs loved nothing more than taking on other canines – and even larger predators like pumas.

Male Cordobas were notoriously vicious, sometimes attacking and killing females during mating. Their hostility extended to people as well, making them dangerous companions. Though occasionally used for hunting, they were never kept in packs because they preferred a fight over a chase; typically only a male‑female pair was employed, with no guarantee they wouldn’t turn on each other.

Because they fought to the death and reproduced slowly, their numbers stayed low. When dog fighting finally became illegal, the breed slipped into extinction.

9 Asil

The Asil, also known as the Aseel, is the oldest chicken breed specifically cultivated for cockfighting. Originating in India over two millennia ago, generations of selective breeding have equipped it with razor‑sharp spurs that never need artificial enhancement – they’re simply covered in tape for the bout.

These roosters boast powerful legs, beaks, and thick necks, and they’ll fight for days without backing down. Weighing between 1.8 and 2.7 kg (4–6 lb), they deliver hefty blows, though that mass also makes them slower. Even as chicks, Asils display the same ferocious spirit, beginning mock battles just weeks after hatching.

8 Lusitano

In Spanish bullfighting, the picador rides a Lusitano horse while thrusting a pike into the bull’s neck. The horses are sometimes blindfolded, other times left to dodge the bull’s horns on their own. Lusitanos are prized for their bravery, calm demeanor, and lightning‑quick reflexes – they never bolt, often charging toward the charging beast.

One legendary Lusitano, Cagancho, spent 11 years in the arena, confronting more than 1,000 bulls across Spain, Portugal, Mexico, and France. Most Lusitanos meet the same fate as their riders when they age out, but Cagancho was spared, retiring in 2002 and passing away from a stroke in 2015.

7 Betta

The Siamese fighting fish, better known as the Betta, earned its moniker from the warrior tribe called the Bettah in historic Siam (modern‑day Thailand). Since the 1800s locals have pitted these flamboyant fish against one another, initially for brief skirmishes that lasted only minutes.

Breeders soon began selecting the most aggressive specimens, extending fights to hours. Victors – usually the largest fish – were removed to recover before being matched against other champions. High‑stakes gambling surrounded these bouts, with wagers ranging from cash to property, and even families wagering spouses.

The king eventually licensed the fish, cementing its status as a regulated combatant. Today, Bettas continue to be raised for fighting, though many are discarded once their battle days are over.

6 Bull And Terrier

The Bull and Terrier, not to be confused with the modern Bull Terrier, was a dedicated fighting dog created by crossing a bulldog with a terrier. When bullbaiting was outlawed in England in 1835, dog fighting surged, prompting breeders to craft a swift, lightweight dog that could endure prolonged bouts and be easily concealed from police.

By blending the Olde Type Bulldog with various terriers, they produced a canine that combined the terrier’s speed and alertness with the bulldog’s power and high pain threshold. These dogs fought to the death. In 1850, James Hink further refined the line, giving rise to the Bull Terrier with a longer head and without bow legs. Early names for the breed included Hink’s Breed and the White Cavalier.

5 Samurai Spiders

Every June, residents of Kajiki, Kagoshima, Japan, stage spider battles known as kumo gassen. Two female Argiope amoena – nicknamed “samurai spiders” – are pitted against each other in a contest that has endured for more than four centuries.

Participants either capture or purchase the spiders and spend weeks training them. The fights are not to the death; a human referee steps in whenever the combat becomes too messy. A spider can claim victory by being the first to bite, ensnaring its opponent in a web, or destroying the rival’s web. Legend says the inaugural battle was organized by military commander Shimazu Yoshihiro to boost his troops’ morale.

4 Miura

The Miura bull is one of Spain’s most formidable fighting breeds, raised on a historic ranch near Seville that originally belonged to Don Eduardo Miura Fernández. The first Miura entered the arena on April 30, 1849.

These bulls are massive and notoriously aggressive. Notable individuals include Murcielago, who survived 24 stabbings from a picador in 1879, and the infamous Reventón and Islero, both of which killed bullfighters inside the ring.

Lamborghini has drawn inspiration from the Miura lineage, naming several of its models after the bulls and reportedly adopting the iconic bull logo after a visit to the ranch.

3 Kelso

Kelso cocks are a line of cockfighting chickens originally fashioned by Walter Kelso. He built his gene pool by purchasing winning roosters from the ring and cross‑breeding them with assorted hens, favoring hybrid vigor over pure‑line breeding.

Kelso’s method involved pairing a new cock with the sister of any of his champion birds; if the offspring proved formidable, their sisters were retained for future crosses. After the death of fellow breeder John Madigen in 1942, Kelso and Bill Japhet inherited his stock, further enriching the lineage.

Today, the Kelso lineage has spawned several sub‑breeds, including the Firebird Kelso in the Philippines – cultivated by Sir Biboy Enriquez, hailed as “the Kelso Man of the Philippines” – as well as the Dink Kelso and the Out‑and‑Out Kelso.

2 Lottatore Brindisino

The Lottatore Brindisino, also called the Brindisi Wrestler Dog, is a freshly minted breed from Brindisi, Italy. It emerged from a deliberate cross of Pit Bulls, Cane Corsos, and Rottweilers – dogs that were already seasoned in underground dog fights.

Because the breed is still unstandardized, individual breeders produce varying versions. In Italy, the dogs are primarily employed by the local Brindisi mafia for clandestine dog fighting, though they sometimes serve as property guards. The breed is notoriously violent and difficult to control; while it may be affectionate toward its owner, it shows little tolerance toward strangers or other canines.

1 Old English Bulldog

The Old English Bulldog earned its name from the brutal sport of bullbaiting, where several bulldogs were unleashed on a tethered bull. Victory went to the dog that seized the bull’s nose and pinned it to the ground.

When bullbaiting was outlawed in 1835, the breed nearly vanished. Some were shipped to the United States, where they were used to capture wild bulls by holding the animal’s nose until a rope could be secured. Later, the Old English Bulldog was cross‑bred with the pug, creating the Olde English Bullogge – a smaller‑mouthed, shorter‑statured cousin that could not endure the rigors of being tossed around by a bull.