In the latest update of Destiny 2, specifically within Heresy Act III, players can discover six Taken Osseous Fragments. Unlike previous additions that required exploration in the Nether, these collectibles are now hidden throughout the new Sunless Cell Strike. Successfully collecting these Fragments and finishing the Strike is crucial for upgrading the Barrow-Dyad Exotic SMG.
Guide to Taken Osseous Fragment Locations in Destiny 2’s Heresy Act III
Requirements to Start
Before you embark on this quest, ensure that you have acquired the Dyadic Perfection Exotic quest from the Slab: Ambition path. If you haven’t already, you may need to complete the initial two Catalyst steps, followed by the week 1 seasonal step for Act III.
Location 1: First Fragment

To find the first Fragment, start the Sunless Cell Strike from the Last City map on any difficulty. Proceed straight down the hallway, and you will encounter the Fragment behind an iron gate at the hallway’s end.
Location 2: Second Fragment
Continue following the marker until you reach an intersection that leads to three pathways. The right path will guide you towards the Founts. As you move right, keep an eye out above you.

Once you’ve climbed upwards, the second Fragment will be found on the upper level.
Location 3: Third Fragment
As you navigate towards the Founts, avoid taking the left route and instead drop down through the large opening in the floor, leading to an underground area.

Once below, take your first right and head straight past two illuminated lanterns. As you enter a section lit by yellow lights, glance to your immediate left for the Fragment, which should be hidden behind some crates.

Location 4: Fourth Fragment

Proceed to the “Asylum”area, where you must eliminate two Taken Breaches positioned at opposite ends. For the fourth Fragment, take a left from the stairs at the entrance, and you’ll discover it at the end of a narrow path joining the wall and stairs.
Location 5: Fifth Fragment
To find the fifth Fragment, return to the stairs from the fourth Fragment and descend. While going down, look left and summon your Ghost. This will reveal hidden platforms below.

Jump onto the longest platform and search for an opening to enter to obtain the fifth Fragment.
Location 6: Sixth Fragment
After vanquishing the Servitor and the Taken Ogre boss, continue following the objective marker. You’ll eventually reach a chamber adorned with hanging Hive Lanterns.

Here, instead of taking the right path, jump up onto the ledge directly before you at the intersection. The final Fragment will be located atop this ledge.
Collecting all six Fragments is essential for unlocking the full potential of your Barrow-Dyad Exotic SMG in Destiny 2. Happy hunting!