Like the normal Atropus planet, Atropus Seas are an unholy, sprawling mass of dead tissue, with flesh-creatures and a psychological assault of the character being your main threat. The main takeaway here however is that rather than being a large unbroken mass of flesh, it's mass largely consists of various bodily liquids along the surface, with small islands of flesh being your only solid ground.
This ocean has two layers of infinite liquid (one near the surface, another below it), where each layer can be either Pus or Blood. It's possible to find an Atropus Sea with only Pus, or only Blood, or Pus/Blood, or Blood/Pus.
Details
Name: Atropus Sea
Tier: 4 - 6.4
Found around stars: Binary Star, Red Star, Blue Star, Dying Star