SP42 Cobra

The SP42 Cobra, formally known as the Special Purpose-42 Main Battle Tank, is an anti-vehicle/anti-fortification vehicle used by the UNSC Marine Corps.

Background
Unlike many vehicles, the Cobra fills two distinct roles, that of a mobile anti-vehicle platform and that of a self-propelled artillery piece. Although it is not fast, the Cobra is still highly maneuverable, and can keep up with combat groups. Despite its heavy firepower, it has relatively poor armor.

The SP42 Cobra is equipped with a pair of LRG Rail Guns on its turret that fire high-density ferrous slugs - which are twice the size of those used by the M68 Gauss Cannon - designed to penetrate enemy armor using sheer kinetic energy. These weapons have a slow rate of fire. The rail guns fire intermittently, not in a single burst, as the energy required to accelerate the slugs to the speeds required to pierce the heaviest armor can only be managed for one of the cannons at a time. Synchronized fire from both gauss cannons will destroy even the most heavily armored tank, with penetration that easily outguns the standard 90mm cannon of the M808B Main Battle Tank.

In addition to the Cobra's anti-vehicle role, crew can stabilize the vehicle upon the ground, "locking it down", and deploy an arcing-trajectory M98 105mm light rail gun which fires a conventional explosive shell at supersonic velocities. The explosive and kinetic forces of the shell complement each other to increase the damage inflicted. When fully upgraded with the 'Piercing Shot' upgrade, one shot on the Normal difficulty has enough power to penetrate the shield mounted on a Locust and destroy it, while one shot can disable the shield on an upgraded Wraith and deal minor damage. In addition, the Cobra, when commandeered by Spartans and after acquiring about 15 stars, is capable of destroying a Scarab in just two shots. It sacrifices mobility for the range that elevating the heavy weapon can offer. The shells used are multipurpose, and can be adapted to eliminate anything from a formation of Covenant Wraiths to a squad of infantry. However, its use against groups of infantry may be less effective if they are spread apart, due to its small blast radius. Cobras can attack only ground units and are specifically designed to engage vehicles, so they are mostly vulnerable to Hunters and Banshees.

Upgrades

 * Deflection Plating: gives the Cobra extra protection. Cost 400 resources.


 * Piercing Shot: enables railgun to penetrate multiple targets, damaging each. Cost 900 resources.

Trivia

 * The vehicle was originally described as being similar to a Russian 'Katyusha' rocket artillery vehicle, which was spurred on by the appearance of vehicles similar to the Wolverine but possessing a different ordnance rack. This was a case of mistaken identity, as the vehicle sighted was actually a Wolverine, but with an upgrade adding a second missile pod, creating confusion.
 * The Cobra's artillery mode has an uncanny resemblance to the Terran siege tank from Starcraft, which can transform from tank mode to siege mode, with a sacrifice of mobility for longer range and greater firepower.
 * Like most UNSC vehicles, the Cobra is superficially similar to its animal namesake. When locked down, the Cobra lowers itself and becomes poised to fire; this is similar to actual cobras, which typically coil before striking. The SP42 is especially similar to the spitting cobra, which can project venom to great distances.

List of appearances

 * Halo Wars