From Halopedia, the Halo wiki
Ghostpierce is a bespoke fireblade, employed as the signature weapon of Jega 'Rdomnai. It began as an untested bloodblade during 'Rdomnai's service in the Covenant's Silent Shadow. After the Sangheili miraculously survived a deadly explosion during a high-priority hunt for a pair of Spartan-III headhunters, 'Rdomnai made sure that the remnants of his weapon underwent the same transformation as he did. He brought the surviving hilt to the artisan armorers of Cherras Keep who reforged it as Ghostpierce. The weapon was then mounted onto 'Rdomnai's robotic arm, ensuring the blade and its owner remained inseparable.
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