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The answer Khan was waiting for seemed to have arrived. The Empire's history with the Nak was old, far older than the First Impact. However, its records could become contemporary if Khan added them to his new knowledge.
Moreover, the Thilku lacked the Global Army's in-fighting and political conflicts. They didn't have opposing parties and conspiracies. Their approach was more straightforward, so Khan could obtain unfiltered and transparent information if the Empire granted those authorizations.
Of course, things couldn't be that easy, and one look at Amox revealed complicated aspects of the topic. The Thilku was hesitant and conflicted, telling Khan he lacked the power to authorize such an endeavor.