Lexus has returned to the Nürburgring with a modified LFA tester wearing a red-and-white color scheme. At the track for the ‘Ring’s industry test week, this LFA was spied testing along with several other supercars. Despite how good it looks with all the added aero goodies, this prototype will probably remain a one-off, according to our source. At first glance, the car appears to be the ultra-exclusive Nürburgring Edition model. But the “AD-X” markings on the side reveal this tester is likely something even more extreme. To show off its carbon fiber body, the LFA’s roof, pillars, and rear spoiler are left unpainted. The front splitter juts out further than on other models, and the bodywork in general appears similar to the turquoise-colored mule we spotted earlier this year. The standard LFA’s 4.8-liter V-10 pumps out 552 hp and 354 lb-ft of torque, and our spy shooter estimates this AD-X model is packing closer to 600 hp. In addition to the Lexus, a Mercedes-Benz SLS AMG Black Series and Audi R8 GT test mule were captured testing at the ‘Ring this week. Check out all the images below.