beams on both sides of the course that keep them in place. Rich merchants from cities in the clouds or asteroids with almost uninhabitable environments invested their wealth in the construction of racing circuits. Some cities have multiple circuits—circuits not used for the Grand Prix are open to pilots for practice. The dynamic structure of the courses are colossal in scale, as most circuits feature a single lap that spans over six miles (10 km). The vehicles used to race in these video games are known as "F-Zero machines", which are designed to hover instead of travel on wheels. An anti-gravity unit, known as the "G-Diffuser System" (first used by the Star Fox franchise's Arwing), allows an F-Zero machine to drive at high speeds while retaining a hold of the track, located from a few inches to a foot below it. However, the slip zones, also referred to as the "magnetic field block coat" in the first F-Zero game, blocks the vehicle from retaining a hold on the track. The racing machines developed for these tracks used the latest in this magnetic technology, and are able to perform tune-ups. Out of the over forty-four known machines, only five do not weigh over a short ton. F-Zero machines have a maximum speed exceeding that of sound. This is possible due to the ultra-compact micro-plasma engines used by the machines. Each machine has four basic performance attributes: body, boost, grip, and weight. Body, boost, and grip are rated on a scale from A to E (A being the best, E, the worst). The higher a machine's Body rating, the more durable it is and the less damage it will sustain in a collision. Machines with a good Body rating are, therefore, able to withstand more attacks before exploding. The Boost rating takes into account the duration of a vehicle's boost, and how great a speed increase it provides. A machine with a high rating can travel at higher than normal speeds for a longer period of time. Grip determines how well a machine negotiates turns. A higher Grip rating means that the player's vehicle will execute steadier turns, while a low one will cause the vehicle to drift more, especially when turning tightly. Weight affects a vehicle's acceleration, grip, cornering ability, maximum speed, and the amount of damage it sustains in a collision. A lighter vehicle is superior in the first three