You'll need to find the Sunless Cell fragments in Destiny 2 if you want to complete the Dyadic Perfection quest and earn the final intrinsic upgrade for the Barrow ...

The last few upgrades for Barrow-Dyad are now available in Destiny 2's Heresy episode. Unlocking the last few upgrades for this weapon will require you to acquire a new set of Taken Osseous Fragments ...

Getting your hands on the Graviton Spike is the first step in its upgrade process. Second, go to the Enclave on Mars and craft one. From there, you’ll return to Kepler and hunt for specific items ...