Biomes

	Data is potentially outdated
	Last updated for version 0.19.14.0 Last mentioned in changelog 1.0.13.0 The current game version is 1.3.0.4 Stub Notes: Aphotic Plateau, Great Sea and Hydrothermal Wastes sections need more info.

A mock-up of the biomes of Europa, as displayed on the design documentation.

Biomes are the different regions of Europa. Each biome has unique characteristics, such as environmental dangers and creatures, that can determine its danger to submarines and their crews.

Europa's exterior surface is covered in thick sheets of ice, hard as stone and devoid of life. However, under the heavy surface ice, the interior of the moon contains many trenches. The farther submarine crews travel down these trenches, the more flora and fauna they will discover as the water's temperature increases. This is seen in the arrangement of the biomes, with the human-populated Cold Caverns being relatively safe near the surface, and the Hydrothermal Wastes at the bottom teeming with large groups of aggressive fauna, but being almost completely devoid of human habitation.

There are 5 biomes in Barotrauma, each one progressively deeper than the last. Caves, Alien Ruins, Wrecks and Beacon Stations are features all biomes have, though each come with their own unique exploratory hazards in addition to these common features.
In Game Modes other than Campaign, a biome will be chosen to be played at random, independent of the chosen difficulty.

Cold Caverns

The first biome in Europa is the Cold Caverns. Civilization is abundant within the Cold Caverns, as are opportunities to repair Beacon Stations within each passage.

Level generation is typically forgiving, and the low difficulty prevents many of the harder enemies from spawning naturally. Wrecks can only spawn in the "transition" subtype, which has a minimum difficulty of 10%. Such a wreck cannot spawn as a Thalamus. Levels range in difficulty between 0% and 15%.

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  A large colony of what appear to be Feathered Tubeworms, as well as two smaller colonies.

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  A closeup of two large colonies of feathered Tubeworms

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  Three Ice Spires, as they appear on Sonar.

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  Two Ice Spires, as they appear outside the submarine

Europan Ridge

The second Biome encountered within a Campaign is the Europan Ridge. This region is composed of a rocky pack-ice, dotted with various unknown flora. Civilization is still fairly common, but empty geographical features are more likely than within the Cold Caverns. There are several environmental hazards found in this biome. Great currents, powerful enough to move a submarine, are present within the majority of every passage. These currents can be detected on Sonar, and are capable of pushing submarines into obstacles or even into The Abyss. The strength of Currents will periodically wane, allowing subs to push through them. Slime Molds can also be found hanging from the ceilings of some passages. These Slime Molds apply drag to the Submarine, slowing it down considerably.

Ballast Flora Spores are encountered in this region and can be detected on Sonar when a submarine is close enough, or spotted by gunners well in advance of contact. Ballast Flora can also be found suspended within currents, where it is much harder to detect with Sonar.

Large floating Icebergs also spawn within this biome, and much like Ice Spires, are highly visible on Sonar. Unlike Ice Spires, Icebergs are extremely durable and require several railgun rounds to break apart, and they will move up and down as currents change direction.

Additionally, Submarines will encounter Sonar Flora, a purple-pink and pulsating growth that heavily disrupts Sonar. The signature appears as a large red-orange cluster of pips, similar in shape and color to a Black Moloch, or volcano. Levels range in difficulty between 15% and 35%.

Packs of Crawlers commonly spawn in groups of 5-7 and Spinelings spawn in groups of 2-5, with pairs or trios of Armored Mudraptors also spawning regularly. Individual Moloch and Hammerheads will begin to spawn naturally, and Bone Threshers and Tiger Threshers spawn in greater numbers. Within passageways over 25%, Moloch are encountered with increased frequency, and hammerhead attacks become more common.

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  A moderately strong current, as it appears on sonar

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  A large floating Iceberg, as it appears on Sonar

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  Sonar flora, as it appears on Sonar

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  A large Floating Iceberg as it appears externally.

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  Slime Mold, as it appears outside the Submarine

The Aphotic Plateau

3rd major biome in a campaign. A great variety of monsters spawn, monster spawns increased. Civilization is sporadic. Alien Ruins can now be encountered randomly in levels, and Beacon Stations will often have disconnected wires to Installations, making beacon station repairs more difficult. Levels range in difficulty between 35% and 50%.

The Great Sea

4th Major biome in a campaign. The levels have little to no floor, so care is advised because a sinking submarine may fall directly into the Abyss below, often below its Crush Depth, where it can fall prey to Abyss creatures. Floating rocks with Piezo Crystals, Ice Spires protruding from the cavern walls and vertically drifting ice boulders spawn. Molochs (solitary, rarely Black Molochs), Watchers (solitary) and Hammerheads (groups of 1-2, rarely Golden Hammerhead) are common. Players will also be attacked by swarms of Crawlers (3-6), Mud Raptors (2-4), rarely Spinelings (~3-4), and most often single Bone Threshers (spawning alongside 2-4 Tiger Threshers). Ballast Flora is also present, but less common than in the previous biomes. Wrecks are generated randomly throughout the level and they may be host to a Thalamus. Levels range in difficulty between 50% and 65%.

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  Piezo crystals as they appear on sonar

Hydrothermal Wastes

Final major biome in a campaign. Civilization is not present, and players will have to activate Beacon Stations and clear Hunting Grounds to help new settlements appear. Levels range in difficulty between 65% and 80%.

Biome Level Generation Parameters

Biome	Identifier	Difficulty	Commonness	Ice Spires	Icebergs	Caves	Side Tunnels	Abyss Hole	Alien Ruins	Wrecks
										Amount	Thalamus%
Cold Caverns	coldcavernstutorial	-	0	-	-	-	0 - 1	-	-	-
	coldcavernsbasic	< 5%	100	5	-	1	0 - 1	-	-	-
	coldcavernsadvanced	> 5%	100	5	-	2	0 - 1	-	-	-
	coldcavernsmaze	> 8%	25	10	-	3	3	-	-	-
	coldcavernstransition	> 10%	100	5	3	2	1 - 2	Yes	-	0 - 1	0%
	coldcavernsoutpost	-
Europan Ridge	ridgebasic	< 35%	100	-	3	3	2	Yes	0 - 1	0 - 1	10%
	ridgeadvanced	> 25%	50	-	3	3	2	Yes	0 - 1	0 - 1	20%
	ridgeoutpost	-
The Aphotic Plateau	plateaubasic	-	-	-	-	3	1	Maybe	0 - 1	0 - 1	30%
	plateauoutpost	-
The Great Sea	greatseabasic	-	-	5	20	1	1	Maybe	0 - 1	1	40%
	greatseavertical	-	20	5	20	1	1	Maybe	1	1	40%
	greatseaoutpost	-
Hydrothermal Wastes	wastesbasic	-	-	-	-	2	1 - 3	Maybe	0 - 1	1	50%
	wastesoutpost	-
???	endlocationbasic	-
	endlocationoutpost	-