Glow Squid

A glow squid is a squid variant that spawns in dark underwater areas, typically in ocean depths, canyons, and underground lakes. It has an aqua luminescent texture, and is the only source of glow ink sacs.

In Java Edition, schools of 4 to 6 glow squid spawn in water (source block or flowing) in complete darkness in the Overworld below layer 30, except for deep dark and sulfur cave biomes. Unlike most other aquatic mobs, they do not require water or waterlogged blocks above or below their spawning space. In all spawnable biomes, the spawn weight is 10⁄10 and the spawn chance is 100%.

In Bedrock Edition, glow squid spawn anywhere when there's water underground, in schools of 2 to 4 (below a solid roof categorized as cave spawn, while squid are surface spawns) anywhere except deep dark biomes, from Y=-64 to Y=30, in a light level of 0. The spawn weight is 10 in all spawnable biomes except mangrove swamp, in which the spawn weight is 100.