If the BMW M4 Competition isn't brutal enough for you, BMW is cooking up a hardcore M4 CSL with more power and less weight. This marks the first time BMW's beloved CSL badge has been used since the E46 M3 CSL launched in 2004, considered by many enthusiasts as one the best BMW M cars ever made. Judging from these latest spy shots, the hot M4 CSL looks nearly ready for production.

This latest prototype spied cruising on a highway in Germany alongside a regular M4 is fitted with production headlights and taillights. Notably, the rear light graphics have a straighter design compared to the curved look of the regular model's graphics.

The headlights are also partially covered, suggesting the clusters will be redesigned for the hardcore M4 CS. As we have seen on previous prototypes, the M4 CSL features a redesigned version of the standard M4's massive grille with peculiar Y-shaped horizontal slats.

Also setting the M4 CSL apart from its standard sibling are a slew of aerodynamic add-ons, including a ducktail spoiler, new side sills, and a front lip spoiler, dialing up the aggression. A healthy diet of carbon fiber and removing the rear seats will make the M4 CSL considerably lighter than the regular M4.

Under the hood, the M4 Competition already produces a respectable 503 hp and 479 lb-ft of torque from a 3.0-liter twin-turbocharged inline-six, but the hardcore CSL variant is rumored to get a boost up to around 540 hp. While the M4 Competition is available with AWD, the CSL is expected to be offered exclusively in rear-wheel drive with an eight-speed automatic transmission.

Since the prototype looks production-ready, the M4 CSL could debut early next year and go on sale for the 2023 model year. A debut next year would be perfect timing as it would coincide with the 50th anniversary of BMW M.