The Obsidian Tribunal is an entity or faction mentioned during Sliske's Endgame if you raced against Saradomin and he won. Virtually nothing is known about the Tribunal, save that they control a host of worlds, on one of which they held Adrasteia, Saradomin's daughter. Nex discovered her there and rescued her, holding her within the Frozen Prison, so Zaros could use her as an bargaining chip if Saradomin won the Stone.
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