There are dozens of powerful nightmare enemies on the decayed Leviathan in Destiny 2’s Season of the Haunted. You need some of them for the Reaper title; others are explicitly designed to earn triumphs. Nightmare of Qalec the sniper falls into the latter category based on our quests this first week.
If you defeat the Nightmare of Qalec, the sniper will bring you the Drainage Triumph on the second page of the Decayed Leviathan section of the Season of Haunted Triumphs section.
You can find the Nightmare of Qalec in the Royal Pools in the hole surrounded by corruption in the back right of the area. You would have gone this route if you were collecting Calus Bobbleheads, as the alcove deep in the area contains the trinket.
However, Qalec will not always be there. As a world boss, he spawns on a timer and will not go away until defeated. The timer only resets when he dies. So if you enter the Royal Pools just after another Guardian kills him, you’ll be waiting for your chance for a while.
Pay close attention to the lower left side of your screen above your skill bar. When the message “A red laser briefly passes through your mind” appears, the nightmare of Qalec is haunting the location. Before you can get to him, you’ll need to deal with psions, legionnaires, and warhounds with orange and yellow bars. All of them are minor Nightmare enemies, so they drop Unstable Essences when killed, making Qalec easier to damage.
Qalec himself can take quite a bit of damage, and his buffs are constantly spawning in, so you’ll need to clear them for uninterrupted access to the boss. Both Qalec and the mobs in his area are said to have 1640 strength, although they don’t hit quite as hard as an enemy in a GM Nightfall or other high-power activities.
Use any means at your disposal to burn the nightmare of Qalec and you will have the draining triumph in due time. There are also no respawn restrictions, giving you as many tries on the guy as you need.
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