The Grav Runner is the cockpit of the Battle Arachnoid, consisting of 34 non-minifigure parts. Its windshield is marked with a Code Brick, which would unlock the Battle Arachnoid's data on the Exo-Force website. This small hover vehicle is powered by twin flame engines. A green orb underneath the vehicle is depicted in the instruction manual as containing a skull, incidentally resembling a Mind Control Orb; however, most official images and the instructions' part list instead place this skull in the Battle Arachnoid's mini-robot.
The Grav Runner is manned by a Devastator robot during the Deep Jungle storyline. It can detach from the Battle Arachnoid to function as a smaller aerial attack vehicle. In its Code Brick description, the Grav Runner is referred to as a "short-range air fighter".[source?]
In 4850307 LEGO Battles, the Grav Runner is the Mounted unit in the Alien army. Despite being a vehicle, it is classified as a minifigure unit rather than a special unit, and therefore is built from Breeding Pits at the cost of 250 bricks. The Grav Runner's stats are 3/5 strength, 350 life, and 4/5 speed, making it fairly fast and battle-effective when attacking in close-range in a group.