Orca 2. Aphotic Plateau. Balance: 16,800 Marks.
Barotrauma is a series of maps, each of which may have one or more objectives on it. The start and end of each map may have a station to dock at. The maps themselves are procedurally generated; they inherit certain characteristics from their biome, but are unique to the playthrough.

Biomes tweak a lot of settings for map generation. The style of caves, the monster spawns, the mineral deposits, even the background art.
We have completed the journey from the second biome, the Europan Ridge, into the third, the Aphotic Plateau. I’m imagining a travel brochure selling the destination as follows.
Husk-Infested Beacon Stations
The beacon stations are much more likely to have former human inhabitants wanting to infect you with their parasitic bites.
Don’t forget to carry anti-parasite drugs!
Ever-Present Thresher Swarms
Tiger Threshers are long shark bois that want to get into your ship. Bone Threshers help them achieve this, by being much bigger and better at punching holes in your hull. Both like to pop up all over the place in the Aphotic Plateau.
Fun and Exciting Wrecks to Salvage
Sometimes somebody pays you to get a McGuffin from a wrecked submarine. Sometimes that sub is full of husks, and sometimes, it’s full of carnivorous armored sea lions called mudraptors. Every time, it’s creepy.
New Friends!
Sometimes the easiest way to take a diving suit involves bringing along its former owner.
Spineling Showers
Huge swarms of monsters means a peaceful aftermath full of sinking corpses, punctuated by crewmembers with bad concussions vomiting all over the sub.
Submarine Spa Day
Because eventually all the blood and vomit makes it hard to see.
Ghost Ship Tours
I got ambushed by a thalamus, a semi-intelligent organism that takes over submarines and uses them to consume more submarines. The captain nearly died, trapped in a compartment full of water, until the roof conveniently collapsed, allowing escape.
Realizing what we were up against, I used the explosive ammo in the bottom gun to scour the aggressor clean. A boarding party went in to investigate but found nothing alive.
Thankfully.
Indiana Jones Moments!
Aliens inhabited Europa a minute ago, but mysteriously left, because of course. And so now humans pay other, stupider humans money to go into these ruins and fetch things. And that stupid human is me.
Here we see multiple near-death moments, including:
- several encounters with the fractal guardians, which are the biomechanical servants of alien origin
- poor choice of weaponry in my bringing a two-handed grenade launcher to what became a series of close-quarters scuffles
- a near-bite encounter with a husked human, saved by my comrade’s shotgun
- near-death flailing under a barrage of swarm feeders, realizing that I was out of ammo, and my AI companion was very stupid
- another husked human ambush that ended in a bite and an infection
“My throat feels sore,” says Azul Blakley, my backup. That’s a sure sign of husk infection. I check our collective pockets, but neither of us have anything to stop or slow the parasite.
We were deep in the ruins and needed to get back fast. I used a tool to cut through layers of walls, heading directly for open water.
“There’s s— moving in my thr—.” Azul is rendered mute by the parasite growing in the back of her mouth. We’re running out of time before the seizures and death.
After cutting through three walls, I see open ocean. I send Azul back to the sub, where the doctor immediately injects her with the anti-parasiting drug calyxanide, saving her.
Megafauna Safari

This is a charybdis. It is dead. It is very large, and is almost as big as the submarine.
Let’s see how we got here.
I took a contract to gather some resources from the abyss, the region at the bottom of the map with two main dangers. First, there are gigantic monsters actively patrolling, ready to smash your sub. Second, being at increased depths exposes you to higher pressures.
My strategy was simple: sneak in, get the resources, get out. I would turn off the reactor and use a sonar decoy to get away at the first sign of trouble. I’ll keep the sub moving slowly and quietly, using passive sonar if possible.
Just as I sidle up next to my target, the sonar scope shows orange waves of echolocation. A ping. A roar. From a monster.
I drop the sonar decoy, turn on the batteries, and run. Another ping. And another, closer. The thing is closing in on us, and it looks like our subterfuge is foiled.
The ship is near an island, a projection of rock. The captain perches the ship on top of it, in the hopes it’ll protect us from uncontrolled sinking.
The monster strikes. All crew go to guns or fixing leaks. The first blow nudges the ship, but the repairs keep it from sinking, and the autopilot returns us to the top of the island. The next blow blasts the ship off the island and rips a huge hole, causing the sub to sink past the island.
Fortunately, there is a bottom here! Without this, we would have sunk past crush depth and all have been squished. We’re on the sea floor alongside some volcanic vents, using the top guns to slowly whittle down the beast.
The charybdis rams us to the right until we’re stuck in a little cave. The crew switches to our best, most expensive ammo. We’re down to using just one gun, our weakest, to slowly plink away at its health.
It’s an awkward fight. It’s slow and painful. The sub is flooded and the crews are not able to keep up with the damage. Fortunately for us, we have lots of welding fuel to keep repairing. Unfortunately for the monster, it doesn’t heal.
Eventually, it dies. We take a close-up look at the corpse; its mouth is bigger than a person.
We gather the contracted minerals and leave.
...
We are quite well-financed now. We have plenty of resources for fabricating weapons and ammunition. The submarine’s systems have all been upgraded several times. We even have some fancy alien guns that we haven’t played with yet.
Our main objective now is getting a new submarine. At some point soon, we will need bigger guns to keep the monsters out, and the ocean with them. The Orca 2 doesn’t have much firepower, and our biggest gun is on the bottom, where it’s useless once the ship is flooded and resting on the sea floor.
Onward, comrades. Maybe we’ll find what we’re looking for in the next biome.