Dagda

Dagda was once a minor Goa'uld, formerly in the service of the System Lord Balor. Along with Manannan mac Lir, he was responsible for Balor's downfall. Both he and Manannan divided Balor's resources between them, and these holdings were enough to gain them both admittance to the rank of System Lord. Despite having won enormous power, Dagda was betrayed and killed by Morrigan, who at the time was only an underlord in his service. She killed him during a summit of his underlords with three shots from a zat. His empire and armies passed to the control of Morrigan, as well as the possession of the Eye of Balor. (RPG: "Living Gods: Stargate System Lords")

Dagda and Cuchulainn once allied with Badb against Morrigan, but even their combined forces could not defeat her. (RPG: "Core Rulebook")

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