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Awakening the ancient fortress, the Black Legion fleet then travelled to an Adeptus Mechanicus weapons testing moon in the Lukitar System. This was to be the Imperium's first taste of the unimaginable firepower of the fortress. From a distance of several million miles, thought to be well beyond effective weapons range, the Blackstone Fortress unleashed a bolt of pure Warp-energy that carved through the Mechanicus moon. Those Imperial vessels in the system could only retreat before such a destructive weapon.

Codex: Black Legion 6th Edition Supplement