In the unforgiving depths of Barotrauma, there are few situations as dire as being trapped inside a flooded submarine with monsters either clawing their way inside or already lurking within. This guide focuses on mastering situational awareness and outlines a strategic approach to surviving catastrophic emergencies, especially those that unfold while stranded at the ocean floor.

Power Systems: The Beating Heart of Survival

When chaos erupts and your systems begin to fail, your first focus must be restoring your offensive capabilities. While you’re technically able to swim outside and confront monsters in hand-to-hand combat, this is rarely viable. Instead, prioritize getting your turrets back online. Doing this requires a basic understanding of how Barotrauma’s internal wiring and power distribution systems function.

Everything aboard your submarine—from turrets to pumps—is wired into an intricate web of interfaces and machinery. You can actually see this complex system in-game, and it’s not just decorative. To get a clearer look, use the submarine editor and switch into wiring mode. Here, you’ll observe the entire power network, beginning with the reactor, which serves as the genesis of all energy.

The reactor feeds power into junction boxes, which then distribute it to various systems throughout the vessel. If the reactor fails or a critical junction box is damaged, the entire system will grind to a halt. This will leave your boat dead in the water with no way to fight back. Your immediate priority should be repairing the reactor and any key junction boxes—especially those that power your pumps and supercapacitors.

To repair systems quickly, equip high-quality tools, invest in relevant talents, and take advantage of the mini-game within the repair interface. Click the repair button precisely when the white line lands in the highlighted zone to maximize your repair speed.

If power still isn’t returning after repairs, revisit the reactor and confirm it has a fuel rod that’s not completely depleted. Avoid loading multiple fuel rods at once—although possible, this dramatically increases the risk of a meltdown. If you do insert more than one, monitor the system closely.

Establishing a Recovery Priority Order

Once your power is stable, bring your weapons systems online to deal with any external threats. After eliminating the monsters, continue the following triage order:

1. Power Systems (Reactor + Junction Boxes)
2. Weapons and Defensive Systems
3. Hull Integrity
4. Pumps and Ballast Systems
5. Navigation/Engine Control
6. Auxiliary Systems (Sonar, Fabricators, etc.)

However, plans don’t always go smoothly. If enemies break into the submarine, defending yourself becomes the top priority. Crew members may also fall unconscious during the chaos. In that case, shift your focus to reviving them—two active crewmates are better than one.

Deadly Exceptions That Break the Rules

There are two notable exceptions that demand immediate changes in your approach:

1. The Black Moloch – This unique variant emits an EMP pulse that disables all systems and drains supercapacitors, making it impossible to bring weapons online. Your best bet is to shut down the reactor and remain completely silent. Once the Black Moloch leaves, cautiously begin repairs.
2. Thalamus Wrecks – If you encounter a Thalamus-controlled wreck and are being assaulted by flesh guns or impaled by flesh spikes, you need to abandon standard repair routines. Instead, aggressively locate and destroy the Thalamus brain. Flesh spikes continuously spawn hostile cells, and flesh guns cause permanent breaches. Once the threat is neutralized, you can return to the usual emergency response order.

Preventative Measures for the Worst-Case Scenarios

To avoid a full-blown disaster, early intervention is key. Rapid sinking is an issue that can quickly spiral into catastrophic flooding. Your first move should be to close all doors and hatches. The more open paths water has to travel through, the faster your submarine will flood.

Of course, you’ll need to enter flooded compartments for repairs. When doing so, make sure to close all doors behind you. Once you fix the breach, reopening the doors that direct water toward your ballast pumps will drain your vessel much more efficiently than relying on minor automated drains.

If you’re the captain during a flooding event, steer the submarine in an upward trajectory. This helps your pumps expel water more effectively and may reduce your descent rate. When possible, turn off the active sonar—this decreases the likelihood of attracting additional monsters. That said, if your vessel is under attack, you may need to keep sonar running to provide Gunners with accurate callouts.

In late-game biomes, sinking becomes almost inevitable. Expect to encounter massive hammerheads and swarms of giant spinelings. In these cases, carrying decoy depth charges is essential. Deploy them at the first sign of trouble. Nearly all enemies will switch focus to the decoy, buying your crew precious time to escape or retaliate.

Final Thoughts

Survival in Barotrauma isn’t just about reacting to emergencies—it’s about preparing for them. By understanding the underlying systems of your submarine, knowing how to prioritize repairs, and adapting to special threat types, you dramatically increase your crew’s odds of survival.

Every second counts at the ocean’s bottom, and being ready before the worst happens might just keep your vessel afloat. Until next time, stay safe out there in Europa’s dark abyss.