You got them from the Halloween boss mode which was just switched over to DH-14 and Pirate not sure if you can get them from anywhere else, Proof...
[ATTACH] [ATTACH] IGN : EvilLarry Sent Xero Discus Custom Exocore to IGN: LordKuma IGN : EvilLarry Received Staff Of Eternity Exocore from IGN:...
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