History of Altars of Sorrow: Brutal Haste

Triumph: "Rapidly defeat a Tier V Nightmare boss." The exact time limit is not given by the sources I opened (the in-game triumph tooltip should show it).

== How to complete ==

Reach the boss tier of Altars of Sorrow with as much timer banked as possible by killing Hive adds and Nightmares quickly.

Have a heavy-damage loadout ready for the boss (e.g. the daily boss's matching weapon) and a Well of Radiance or Tether to amplify damage.

Clear the immunity-phase Nightmares quickly so the boss shield drops fast. It is easiest to do this as a coordinated fireteam.

Completing Altars of Sorrow: Final Phase happens along the way.

Altars of Sorrow is a player-started horde-style public event in Sorrow's Harbor on the Moon, introduced with Shadowkeep. Teams defend altars against waves of Hive and Nightmare enemies (tiers I-V) before a boss tier. The event has not been confirmed here as currently active; sources I opened (Destinypedia, the D2 Wiki, TechBloat) describe the Shadowkeep-era version, and the triumph text refers to "Tier V" and "phases", so check in-game whether it is still available or has been retired or reworked.

== The event in brief ==

• Tiers I-II: 4-5 Nightmares. Tier III adds shielded Wizards that need cleaver drops from Accursed Swordbearer Knights. Tiers IV-V have 7-8 Nightmares and more Wizards.
• The timer starts at 60 seconds. Killing regular Hive adds 1 second, and a Nightmare that reaches an altar and sacrifices itself costs 10 seconds (sources disagree on whether killing a Nightmare also adds time; Destinypedia says it adds 10).
• The final tier is a boss rotating daily: Nightmare of Phogoth (drops Blasphemer), Nightmare of Taniks (drops Apostate) or Nightmare of Zydron (drops Heretic). The boss becomes immune periodically and spawns Nightmares that must be cleared or they sacrifice at the altar.