From Destinypedia, the Destiny wiki
((STEEL MEDULLA~)) is an Exotic Pulse Rifle and the Adept variant of STEEL MEDULLA~ acquired from Wrath of the Machine Heroic Mode by completing Challenge Modes. It can also be obtained by defeating Aksis, Archon Prime in the Wrath of the Machine raid on hard mode. It is a Häkke Herja-D that has been modified with SIVA technology.
List of Appearances