Throughout the many biomes found in various alien seas of Subnautica, the flora and fauna that proliferate the depths are all unique as well as interesting in their own ways. However, some need much more specific conditions to thrive than others; these are species locked to a small number of biomes.
These beings below the waves who appear only in one or two types of biomes number only seven. Many of them are quite dangerous, due to the nature of this world's fauna being aggressive as a result of living in a hyper-carnivorous environment. To get a sense of what threat, or boon, these rarest of creatures possess, players should scan each for valuable data and gain insight on how to deal with them.
7 Blighter
Important Information
- Category - Carnivores
- Tab - Fauna
- Attitude - Aggressive
- Health - 10
- Damage - 7
- Drops - None
- Biomes - Blood Kelp Caves & Blood Kelp Zone
- Active During - Cathemeral (Day & Night)
- Debug Spawn - "blighter"
Like their more common variant, Biters, these toothy Blighters chomp at those close by with proportionally massive teeth. Their dentition is such a dominant feature in their lifestyle that they can't even fully close their mouths, not unlike Earth's Viperfish.
Also similarly to some of Earth's deep-sea fauna, the Blighter has a stalk upon its brow which it uses as a lure to draw in unsuspecting prey. However, this most common of their hunting methods does not mean they won't take a bite out of an approaching player on a whim.
6 Crabsnake
Important Information
- Category - Carnivores
- Tab - Fauna
- Attitude - Aggressive
- Health - 300
- Damage - 35
- Drops - None
- Biome - Jellyshroom Cave
- Active During - Cathemeral (Day & Night)
- Debug Spawn - "crabsnake"
Equal parts hostile and hideous, the Crabsnake is an eel-like sea beast that is only found in a single biome. They spend much of their time dwelling within or around the vibrant undersea mushrooms of their cavern homes. When a player approaches, they will strike fast and hard, so be wary whenever one travels through a Jellyshroom Cave.
This species exhibits novel symbiosis with the Jellyshrooms that grow in their eponymous biomes and actually live within the flora itself. Like many species, they reproduce sexually and their eggs can be usually be found around Crabsnake-populated areas.
5 Crashfish
Important Information
- Category - Carnivores
- Tab - Fauna
- Attitude - Defensive
- Health - 25
- Damage - Depends on one's proximity to their explosion attack
- Drops - Cave Sulfur
- Biomes - Kelp Forest Caves & Safe Shallows Caves
- Active During - Cathemeral (Day & Night)
- Debug Spawn - "crash"
One would not think that this most obnoxious of sea critters is a rare species due to how often it feels like the player encounters them while harvesting resources. Caves can be packed with this kamikaze fish, and they will happily try to take the player down with them at the slightest provocation.
Their Attitude classification is Defensive, as they only attack while one is close to their home, however, Crashfish clearly believe that a strong offense is the best defense.
4 Crimson Ray
Important Information
- Category - Herbivores
- Tab - Fauna
- Attitude - Passive
- Health - 100
- Damage - None
- Drops - None
- Biomes - Inactive Lava Zone & Lava Lakes
- Active During - Cathemeral (Day & Night)
- Debug Spawn - "ghostrayred"
Majestic and beautiful to behold, Crimson Rays are herbivorous creatures that glide about the hottest of areas. They can be found near lava and can blend into their often burning surroundings thanks to their monochromatic red coloration.
Since these wide-finned swimmers are completely non-hostile, it's totally safe to get up close to them and admire their natural beauty; just beware of the nearby molten rock.
3 Jellyray
Important Information
- Category - Herbivores
- Tab - Fauna
- Attitude - Passive
- Health - 100
- Damage - None
- Drops - None
- Biomes - Deep Grand Reef & Mushroom Forest
- Active During - Cathemeral (Day & Night)
- Debug Spawn - "jellyray"
Like many other rays found in the alien seas of Planet 4546B, Jellyrays are relaxed herbivores who mind their own business and subsist off of local vegetation found in the Deep Grand Reefs as well as the Mushroom Forests.
Despite their vibrant shimmer up close, the body of this species is mostly transparent and difficult to see in low-light conditions; a notable trait of their preferred habitats.
2 Floater
Important Information
- Category - Scavengers & Parasites
- Tab -Fauna
- Attitude - Passive
- Health - 40
- Damage - None
- Drops - None
- Biomes - Grassy Plateaus & Safe Shallows
- Active During - Cathemeral (Day & Night)
- Debug Spawn - "floater"
Floaters are invasive yet non-hostile; a strange combination. They attach themselves to anything that touches their body and although they likely do this to feed upon smaller parasites clinging to larger creatures, they surely also do so for a free ride.
While not intentionally aggressive, this can cause some issues, as even a single Floater can vastly pull anything off course, from Reefbacks to submersible vehicles. On the positive side, this same trait has been used by players in emergencies to prevent a Cyclops from sinking due to how buoyant these gelatinous beings are.
1 Sea Dragon Leviathan
Important Information
- Category - Carnivores
- Tab - Fauna
- Attitude - Aggressive
- Health - 5000
- Damage - Bite Attack (instant death), Swat Attack (40), Fire Breath (20), & Meteor Attack (80)
- Drops - None
- Biomes - Inactive Lava Zone & Lava Lakes
- Active During - Cathemeral (Day & Night)
- Debug Spawn - "seadragon"
Easily one of the most deadly species on the planet, this 368 foot-long leviathan can kill unprotected divers instantly as well as severely injure them with minimal effort. Sea Dragon Leviathans can also ravage submersible vehicles; Seamoths and Prawn Suits can get torn up very quickly while Cyclopses get rammed to smithereens.
It is best to avoid this creature at all costs, therefore it being among the rarest of organisms is undeniably a good thing. However, those eager to scan this deep-sea behemoth and complete their data entry collection can potentially find them near lava. Though, be warned, as Sea Dragon Leviathan are extremely hostile.