The Midnight Zone is a layer of the ocean where it transfers between the layer that gets sunlight and the pitch-black void below. This layer of the ocean gives off an almost ultramarine colour. Not much is known about this layer of the ocean, so perhaps many creatures we thought were fiction may live down there, perhaps Mermaids?! Maybe! The slimes colour represents this layer of the ocean and what could be down there, including what may be a lot of our treasures that were swept away with the currents, represented by the bag of glittery treasures you get! It's a super thick and glossy slime with the most vivid Ultramarine blue.