The Four Peaks Treasuries were the four armories plundered during the climax of the battle of Bulao Mountain, at the cost of Yanjun's Divine Soul being heavily damaged by Qin Fangtian. They contained a massive store of cultivation resources, sufficient for the Qinggan faction to recover and rebuild.
Somehow, Jing Ji had managed to secure an amnesty from the Capital, extricating himself from the quagmire of the Qinggan faction while taking the Four Peaks Treasuries with him as his bargaining chip for survival and standing.
In all fairness, Lu Bei desperately wanted those Four Peaks Treasuries. But as for Jing Ji himself...
Chapter 421