From Halopedia, the Halo wiki
"Grave-makers" are rugged, nest-shaped gun platforms that are capable of carrying groups of individuals for surface deployment. They consist of a main body and arms. "Grave-makers" are crudely fused together flying craft that are plated over with heavy armor shielding. Downward-facing engines lift them into the air in sputtering and roaring bursts, which can sometimes be a struggle due to the ships' weight. They are equipped with heavy-grade spike autocannons that provide substantial firepower.
Many "grave-makers" were brought by the Jiralhanae chieftain, Hekabe, to the world of Carrow in September 2558. Carried aboard his flagship, Foebane, they were released from its belly to attack the humans living in the city of Suraka.
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