From Halopedia, the Halo wiki
Gribyam is an Unggoy member of the Swords of Sanghelios and a self-proclaimed biologist. In October 2558 he formulated an outlandish theory about human reproduction, hypothesizing Doctor Catherine Halsey's missing arm to be due to a natural biological process.
His mention of "theories from New Alexandria" may be a reference to Catherine-B320, who was also missing an arm.
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