Thoska Isle is an island in the Ironbound Archipelago in the Steaming Sea. It is an independent island—it does not form part of the Linnorm Kingdom of the Ironbound Islands. It lies between the also-independent islands of Irrere and Mordant Spire. An ancient Azlanti ruin, the Grass-Shrouded Ziggurat, sits untouched since before Earthfall and buried by nature. Its unusual shape is now the only clue to its ancient origin.