Caligo, Miasma of Night

Caligo, Miasma of Night is a Nightlord boss fought during the final day of the Fissure in the Fog Expedition. Her raid is only available in expeditions exclusive to The Forsaken Hollows DLC. She is a four-winged prehistoric dragon with frigid powers, and she counts as an Ancient Dragon, so effects and tools that work well against dragons are especially relevant.

Caligo opens the encounter with a blizzard-like arrival that blankets the arena in thick fog and repeatedly showers the battlefield with ice crystals. These crystals deal damage and build up frostbite, and similar crystals may continue to form during the fight even when she is not actively using that attack. Her breath attack also deals magic damage, applies frostbite buildup, and leaves blue crystals on the ground that explode with more frostbite buildup if stepped on.

Several of Caligo’s attacks are signaled by her shrouding her position in dense mist. One pattern creates a giant ice disk overhead that eventually shatters into falling shards; this can be avoided either by running away from the disk or by moving close to Caligo, where there is a safe zone. Another pattern draws cold winds toward her and brings up large ice pillars, followed by a burst of frigid wind; players can survive by taking shelter behind the pillars. Once she reaches half health, she enters a second phase and gains a new aerial attack in which she flies back and forth over the battlefield, showering the party with ice shards on each pass.

Caligo is vulnerable to a Critical Attack after her stance is broken, so opportunities to posture-break her are valuable. Dealing enough Fire damage will stagger her and inflict a defense debuff for 30 seconds, making fire the clearest way to open offensive windows. Completing the Mountaintop Shifting Earth also provides a useful anti-dragon buff, reduced frostbite buildup, and increased attack whenever frostbite is inflicted on someone nearby, which helps both survivability and damage output in this fight.

A few other details make the encounter easier to read. Whenever frostbite is inflicted during Caligo’s fight, the player’s frostbite resistance is reduced by 15, which makes repeated frostbite procs easier to suffer afterward. Her damage profile is otherwise unremarkable in the available data, but she is fully immune to Sleep.

The raid’s completion reward grants each player a one-time defensive buff: the next time they would take lethal damage, they instead dodge the attack and briefly turn invisible. Caligo’s appearance is framed by the lore as the moment a hidden observer descended from a mountain-like refuge to witness a world-shaping catastrophe firsthand.