From Halopedia, the Halo wiki
Forerunner Council ships were a class of vessel used by the Forerunner Council. They were one of the most advanced ships in the Forerunner ecumene, superior to the most powerful of Warrior-Servant vessels in all but weaponry. The hull of a Council ship has been described as "a double upsweep of winds cast in bronze and gold." Their interiors shared the general aesthetic style associated with the Council; elegant but free of luxury.
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