XM4600 Zeus plasma munition howitzer
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On the M145D Rhino the Zeus cannon is mounted to a large turret, the weapon is capable of traversing upward at a roughly forty-five degree angle. The Zeus 320mm plasma cannon has a range of 100 kilometers, and as with all plasma-based weapons, the Zeus is potent against energy shielding. The weapon operates via use of reverse-engineered fuel rods placed inside a modified artillery shell, fired from a custom-built howitzer.
During the Harvest campaign the Office of Naval Intelligence procured numerous specimens of Covenant fuel rods, and made quick work beginning to reverse engineer it. One project resulted in the M145D Rhino, a basis for the Zeus 320mm plasma cannon, a cannon which could make use and direct plasma energy.
During the Battle for Arcadia, the cannons of five Rhinos in conjunction were used to take down a portion of a giant energy shield, allowing the UNSC Spirit of Fire to take down the Covenant shield generators and air defenses below, exposing the Covenant operation on Arcadia.
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