His car-buying power might not be what it once was, but the Sultan of Brunei remains one of the richest men in the world thanks to his tiny nation's oil riches. His car collection is legendary, and it's one of the largest in the world, with most of his cars being bought throughout the Nineties and into the Noughties. His favorite brands include Rolls-Royce, Ferrari, Bentley, and Aston Martin, and between them, he's spent hundreds of millions of dollars buying cars for himself and his family over the years.

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Many of these cars are special-edition models which were created exclusively for the Sultan himself. They were built in secrecy, shipped to Brunei, and have remained in his private collection ever since, with very few visitors ever allowed to see them. A few of these unique cars have escaped the Sultan's clutches and been snapped up by other collectors, but the vast majority have stayed hidden in the Royal Family's warehouses, where no one apart from the family is even able to set eyes on them.

10 Bentley Dominator

Bentley Dominator - Front View
Bentley Spotting

Ask many gearheads what Bentley's first SUV was, and they'll say the Bentayga, but there was in fact one that was produced decades before. The Dominator was made specifically for the Sultan and his family, with six units commissioned for $4.6 million each.

Bentley Dominator
Via Bentleyspotting

Not much is known about the specifications of the car, but it's thought that the Dominator borrowed heavily from the Range Rover of the era. Under the hood was either Bentley's 6.7L V8 or Land Rover's 3.9L V8, but it's unconfirmed which one.

9 Ferrari F50 Bolide

Ferrari F50 Bolide
Via Drivetribe

Rare Ferraris are nothing new, but this special-edition F50 is so rare that only a few grainy photos of it are known to exist. The story goes that the Sultan wanted a unique supercar based on Ferrari's already-rare F50, but rather than base it on the chassis of a standard F50, the Bolide used the chassis of an F1 car.

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Ferrari F50 Bolide
Via Drivetribe

It reportedly features the bare necessities to make it road-legal and has a full carbon-fiber chassis and twelve-cylinder engine. Other than that, almost nothing is known about the car, a testament to just how much influence the Sultan had on the fabled Italian manufacturer during his peak car-buying period.

8 BMW Nazca M12

BMW Nazca M12
Via BMW Media

Originally unveiled in concept car form by BMW, the Nazca M12 was arguably the closest BMW ever got to making a true successor to the M1. The car used the same V12 engine as the 850i of the era, making around 300 horsepower.

BMW Nazca M12
Via BMW Media

The original concept car is still under BMW's ownership, but reports suggest that the Sultan paid Italian coachbuilder Italdesign an undisclosed sum of money to make a second version specifically for him. Only one alleged photo of this second M12 exists, but if it's real, then it's the only privately-owned M12 in the world.

7 Aston Martin AM3

Aston Martin AM3
Via Aston Martins

The AM3 was unusual for Aston Martin, as it was bodied by Pininfarina in Italy, featuring a notably different design to the company's other cars from the era. It was based on a Vantage chassis and featured Aston's 5.3L V8 engine, although the exact power output is unknown.

Aston Martin AM3
Via Aston Martins

None of the cars have ever been seen in public and the only known photos of them were taken in or around Pininfarina's factory in Turin, Italy. It's thought that the cars are likely to remain in the Sultan's warehouse, perhaps having never been driven.

6 Bentley Buccaneer

Bentley Buccaneer
Via Bentleyspotting

The Sultan's collection is so large that it's very likely he can no longer remember all the cars he's bought, but the Buccaneer is reportedly one of his long-term favorites. It's been spotted several times driving around Brunei, which in itself is a rarity as many of his cars have never been seen.

Bentley Buccaneer - Front Quarter
Bentley Spotting

Not much is known about the specifications of the car, but it's thought to have the engine from the Continental R of the era. Six examples were reportedly produced in black, red, and silver, and all of them are still under the ownership of the Sultan and his family.

5 Leblanc Mirabeau

Leblanc Mirabeau
Leblanc

Swiss carmaker Leblanc was at one point tipped to be the next big name in the performance car world, but after a failed US market launch, they ran out of money and disappeared into obscurity. That's not before selling several examples of their ultra-rare Mirabeau to the Sultan and his family.

Leblanc Mirabeau
Via Leblanc

Like with many of these secretive deals, the details of exactly how many cars were bought are unclear. However, it has been confirmed that the car shared its V8 engine with the Koenigsegg CCR, so it would have been mind-blowingly fast to drive. None of the Sultan's Mirabeaus have ever been seen in public.

4 Ferrari Testarossa F90 Speciale

Ferrari Testarossa F90 Speciale
Via Supercars.net

Another of the Sultan's special-edition Ferraris, the Testarossa F90 Speciale was, as its name suggests, based on the Ferrari Testarossa. The car was produced in a limited run of six units in 1988, but it took a further 18 years for Ferrari to officially confirm their existence.

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Ferrari Testarossa F90 Speciale
Via Ferrarilife

It's reported that the cars were essentially stock Testarossas underneath, sharing the standard car's 390 horsepower flat-12 engine. Pininfarina was then in charge of rebodying the car to the Sultan's exacting tastes.

3 Bentley Java

Bentley Java - Front Quarter
Bentley

The Java was created at a time when Bentley was doing some soul-searching about how to make itself appeal to a more modern kind of buyer. It was initially created as a design study and never intended for production, but when the Sultan saw it, he wanted his own.

Bentley Java
Via Reddit / Icemanjoe

Bentley obliged, and eventually, eighteen examples of the car were built, with each one going to the Sultan or a family member. A few examples have been spotted in private garages in Hong Kong, but they've never been spotted actually driving on a public road.

2 Mercedes-Benz S73 T AMG Wagon

Mercedes-Benz S73 T AMG Wagon
Brabus

This is no ordinary Mercedes station wagon, as it features a 7.3L V12 under the hood, the same engine that also powers the Pagani Zonda. Yes, it's a Zonda-engined 200+ mph S-Class wagon. Of course, the only man with enough influence to get Mercedes to make something as mad as this was the Sultan, and it's thought that several were made under commission.

Mercedes-AMG S73 T Wagon 2 Cropped
Via Facebook / Brabus 7.3 T

It's not known exactly how many, and according to The Drive, it's rumored that AMG has kept at least one example of this crazy car in storage at their headquarters, although they've always refused to confirm this. Fingers crossed they bring it out for the rest of us mere mortals to enjoy one day.

1 Ferrari FX

Ferrari FX
Via Supercars.net

Before the FXX or the FXX-K had even been conceived, the FX was one of the jewels of the Sultan's collection. The car would have probably joined the ranks of vehicles that were never seen in public, were it not for the Sultan running out of money halfway through the car's production run.

Ferrari FX
Via Supercars.net

Seven examples were commissioned for an undisclosed sum, but the Sultan could only afford to pay for four of them. The remaining three were then sold off to different buyers who keep them stored in private collections, far away from the public eye. The Sultan's lack of funds to pay Ferrari marked the start of the decline of his buying power, and now it seems like most of his collection has been left to rot, as he's reportedly been unable to pay for the upkeep of the majority of cars in his possession.