History of Chosen Path

Chosen Path is a triumph worth 20 points: complete the quest "The Taken Path". It is one of the triumphs of the Heretic seal from Episode: Heresy.

How to complete

1. Start the quest. It is hidden: during a run of The Nether, find the Taken Blight (it can spawn in the Mausoleum, Hall of Souls or Trenchway) and jump into it. Stand on the floor plate, follow the direction the combat log whispers, and take the Taken Osseous Fragment from the hidden room.
2. Take the fragment to the Shaping Slab in Eris Morn's apartment in the Last City to pick up The Taken Path.
3. Per Dexerto and The Gamer, the quest chain then has you collect fragments from lost sectors (K1 Revelation and Veles Labyrinth), finish three curse objectives (Altars of Sorrow, Hallowed Grove, Nightmare Hunt: Pride), and activate three hidden statues in the Nether to spawn minibosses.
4. Finish with the Derealize Exotic mission. Completing it awards Barrow-Dyad and finishes the quest, which completes this triumph.

Rewards

Triumph score and progress toward the Heretic title. The quest itself rewards the Exotic SMG Barrow-Dyad.

Sources describe step details slightly differently (e.g. the second location of the fragments); check the in-game quest log if a step looks different.