Forgotten Deep Solo Mastery

Overview

Forgotten Deep Solo Mastery is a Triumph in Destiny 2 that requires the Guardian to complete the Forgotten Deep Lost Sector on Master difficulty without a Fireteam. The triumph awards 5 Triumph Score. The sector is on the Pale Heart; its enemies are an Arc threat with Unstoppable and Barrier Champions.

A separate triumph, Forgotten Deep Flawless Solo Mastery, covers the flawless version of this run.

How to complete

1. Launch the Forgotten Deep Lost Sector on Master difficulty and make sure no other Guardian is in your group. The recommended power for Master is 2050.
2. Master drops for solo Exotic armor are rated Common, and the weapon drop chance is 100% once all champions are eliminated.
3. Barrier champions: damage them first, then shoot the barrier bubble with an anti-barrier weapon to stun them.
4. Unstoppable champions: stun them, then damage them. Damage dealt while they are not stunned is significantly reduced.
5. Stun options solo: a Strand suspend can disable a group of enemies or stop a charging Unstoppable champion. A Stasis freeze handles all three champion types, and a fusion rifle with Chill Clip is one of the cheapest stuns.
6. Keep heavy ammo for stunned champions and the final boss.
7. Finish inside about 15 minutes. Darkness Encroaching removes all revive tokens around that mark, and solo runs have no teammate revives. Darkness Encroaching is the mechanic behind this limit.

Further reading

A video walkthrough of a solo Master run of this sector is linked in the sources.