Right now, the AMG GT 63 S is the most powerful production car Mercedes currently makes, thanks to its twin-turbo 4.0-liter V8 engine producing a whopping 630 horsepower. Leave it to Brabus, then, to take it to the next level. Debuting at the Top Marques Monaco this week, the renowned German tuner's latest performance upgrade cranks up the super sedan's output to an obscene 789 horsepower – that's 159 more hp than you get in the standard AMG GT 63 S. Torque has also increased to 737 lb-ft.

As a result, the German super sedan will now sprint from 0-62 mph just 2.9 seconds, which is three-tenths of a second quicker than the standard car, before topping out at an electronically limited 196 mph. To achieve this phenomenal performance boost, Brabus had to make some extensive modifications, including installing a pair of larger turbochargers and tweaking the ECU.

As well as improving the performance, Brabus has also given the exterior an aggressive makeover. To help it stand out from the regular GT 63 S, the aftermarket tuner developed several aerodynamically efficient components finished in naked carbon and finetuned in a wind tunnel, including a new front spoiler and attachments for the large air intakes of the bumper, giving the sedan a meaner face. The rear also looks sportier thanks to a rear diffuser housing the quad tailpipes of the tuner's sport exhaust system with titanium finishers.

Elsewhere, the modified Merc rides on a set of 21-inch front and 22-inch rear wheels with a new 10-spoke design. A plug-and-play device for the car's air suspension also allows owners to lower the AMG by nearly one inch, giving the sedan an even more aggressive stance.

Inside, the souped-up sedan features a sumptuous mix of leather and Alcantara materials available in a "virtually endless variety of available colors and upholstery designs". If you want a more premium interior, Brabus is also offering wood or genuine-carbon inlays in a wide range of colors and specifications.

The show car that will be displayed at Top Marques Monaco has been fitted with leather seats covered in perforated black leather and highlighted with white leather elements, along with illuminated door sills with the tuner's logo color matching the cabin's interior lighting. Aluminum door pins and pedals round off the interior enhancements. The Brabus 800 can be ordered as a complete car, or Brabus can convert any current Mercedes GT 63 S 4MATIC+ to the desired performance level.