The Firefly Squid is a small, deep-sea squid found in both games. It is a hidden creature that can only be found under glow points.
They appear in groups.
"The hundreds of light-emitting organs on its body make this squid shine with a bluish-white light.
It has ten arms, but only the fourth pair emit any light; there are three especially bright light-emitting organs at their tips which are used for intimidating other creatures.
It spends the day at depths of several hundred metres, returning to the surface when night falls."
It can sense how much light is coming from the surface and adjust the brightness of the light from its luminescent organs, making it hard for predators to detect it from underneath as its silhouette blends into the background.
These can be found on walls in the Abyss, and very rarely on the edge of the crevasse outside.
These can be found on walls in the Zahhab Region Depths. In the Marine Encyclopedia, their location is marked as the North-Eastern quadrant of coordinate square C-2.