What will become of the 4x4 when something bigger and better comes along? Well there’s nothing to worry about because it isn’t likely to happen anytime soon. Or so we thought, before Mercedes-Benz decided to punch our preconceptions in the gut by introducing its 6x6. The German automaker has launched the G63 - its first six-wheeled model since the World War 2.LIMITED EDITIONThe Daily Mail reported that the automaker unveiled a new rugged off-roader with six wheels - their first since a similar model was produced for the Nazi Germany in the 1930s .The outrageous G63 AMG 6x6 is a limited edition model based on the iconic G-Wagon. It has been designed, the automaker claims, "to have the off-road capabilities of a tank, accelerate like a hot hatch and provide the luxury feel of a limousine."The automaker has replaced the standard G Wagon's three-litre diesel engine with a twin-turbocharged 5.5-litre V8.The result is a 399kW behemoth which is capable of 0-100km/h in less than six seconds - despite measuring 5.7m in length and weighing 3.85 tons.The automaker reckons the 6x6 - which has 37 inch rims - can negotiate rocky terrain with “all the agility of a mountain goat”, while fording a river is “almost child's play”.“Anyone exploring the on-road performance is certain to be impressed by the catapult-like acceleration of this 3.85-tonne pickup.”However, the 6x6 comes with a massive price-tag, the equivalent of about R4.8-million - making it the most expensive model in the Mercedes range and three-times as pricey as a typical G Wagon.The off-roader will be limited to around 30 sales per year, according to the Daily Mail.The new model is not the first six-wheel off-roader from the automaker, with Adolf Hitler owning eight G4’s during the Third Reich.The G4 was a heavy-duty off-road car the automaker produced for the German army between 1934 and 1939. About 57 of these were built during this period with heads of state and top military brass regarding them as a “prestige all-terrain vehicle”.It is understood there are just three models still in existence which are absolutely authentic although other models have been rebuilt. One of these models is owned by the Spanish royal family after Hitler gave it to General Franco in 1939.