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This article is about the recreational narcotics used by Unggoy. For the gel used by the Forerunners and Covenant for energy, see infusion gel.
In 2462, as a revenge for Kig-Yar nest relocations on High Charity caused by the rapidly increasing Unggoy numbers, some radical Kig-Yar shipmasters poisoned Unggoy infusion supplies, making several thousand affected Unggoy males sterile. The Covenant leadership's lack of response to this event, which became known as the "Infusion Incident", eventually caused the Unggoy to revolt, beginning the Unggoy Rebellion.
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