As of my last knowledge update in September 2021, there were several exotic and high-performance supercars in the world. However, please note that the world of supercars is ever-evolving, with new models and designs being introduced regularly. Here are some exotic supercars that were highly regarded at that time:

1.Bugatti Chiron:

The Bugatti Chiron was one of the fastest and most powerful supercars available in 2021. It featured a quad-turbocharged W16 engine with over 1,500 horsepower and could reach speeds well over 250 mph.

2.Koenigsegg Jesko:

The Koenigsegg Jesko was another hypercar with incredible performance. It boasted a 5.0-liter V8 engine with a twin-turbo setup, delivering up to 1,600 horsepower and a top speed estimated to be over 300 mph.

3.Ferrari LaFerrari:

LaFerrari is part of Ferrari’s limited-series production and combines a V12 engine with an electric motor for a combined power output of around 950 horsepower. It was known for its striking design and exceptional performance.

4.Pagani Huayra:

The Pagani Huayra was celebrated for its meticulous craftsmanship and attention to detail. It featured a 6.0-liter V12 engine producing around 720 horsepower and had a unique and artistic design.

5.McLaren P1:

The McLaren P1 was a hybrid hypercar with a combined power output of 903 horsepower. It was designed to deliver astonishing on-track performance while still being a usable road car.

6.Lamborghini Aventador SVJ:

Lamborghini’s Aventador SVJ was known for its aggressive styling and a 6.5-liter V12 engine that produced 770 horsepower. It held the Nürburgring Nordschleife production car lap record at the time.

7.Porsche 911 GT2 RS:

While not a traditional supercar, the Porsche 911 GT2 RS was a high-performance sports car with a 3.8-liter flat-six engine producing 700 horsepower. It was highly regarded for its track capabilities.

8.Rimac C_Two:

The Rimac C_Two was an all-electric hypercar with incredible performance figures, including a claimed 0-60 mph time of under 1.9 seconds and a top speed of 258 mph. It also had a unique and futuristic design.

9.Aston Martin Valkyrie:

Developed in collaboration with Red Bull Racing, the Aston Martin Valkyrie aimed to bring Formula 1 technology to the road. It featured a high-revving V12 engine and advanced aerodynamics.

10.Hennessey Venom F5:

The Hennessey Venom F5 was touted to be one of the fastest production cars in the world, with a claimed top speed of 311 mph. It was powered by a 6.6-liter twin-turbocharged V8 engine.

Please keep in mind that newer and even more exotic supercars may have been released since my last update. Additionally, the availability and production of these cars are often extremely limited, making them even more exclusive and sought-after by collectors and enthusiasts.