If you’ve spent even 10 hours exploring the icy, monster-infested depths of Subnautica 2, you already know the water hides far more threats than just low oxygen or hypothermia. I’ve lost count of how many times I got caught off guard by a shadow leviathan in the first 20 hours of playing, back when I thought a basic survival knife was enough to take on anything. A single unexpected hostile encounter can erase hours of hard-earned progress if you’re caught unprepared. That’s where having the right Subnautica 2 weapons makes all the difference between a successful exploration run and a mad scramble back to your drop pod with half your health gone. I’ve put in over 120 hours in the game so far, testing every weapon type against every hostile creature, so this guide covers exactly what works, what’s a waste of resources, and how to get the most out of every tool you craft.
Core Subnautica 2 Weapons Every Player Should Craft First
You don’t need to unlock every weapon in the tech tree to stay safe, especially in early and mid-game. The three tools below cover 90% of common threats, use easy-to-find resources, and work for every playstyle from casual explorer to hard-mode survivalist.
First on the list is the Thermal Survival Knife, the first weapon upgrade you should craft as soon as you unlock the blueprint. It only requires 1 titanium, 1 lithium, and 2 magnesium, all easy to find in shallow ice caves and coastal areas. It deals 3x more damage than the basic knife, works on small to medium threats like rock punchers and snow stalkers, and even lets you harvest rare creature samples without extra tools.
The second must-have is the Stasis Rifle, a non-lethal tool that freezes hostile creatures for up to 12 seconds at base charge. It’s a lifesaver for leviathan encounters, letting you either escape unharmed or line up attacks with other weapons if you prefer a more aggressive playstyle. You can find its blueprint in abandoned research outposts in the Glacial Basin area, and it only costs 2 wiring kits, 1 titanium ingot, and 1 battery to craft.
The third core weapon is the Propulsion Cannon, which can pick up rocks, debris, and even small hostile creatures to throw at larger threats. It also doubles as a utility tool for moving obstacles blocking cave entrances or salvaging sunken wreckage. Skip the standard dart pistol entirely in early game, it does almost no damage against anything bigger than a bitey fish and wastes copper that’s better used for batteries.
Lethal vs Non-Lethal Weapons: Which Fits Your Playstyle?
One of the biggest questions new players have is whether they should invest in lethal weapons or stick to non-lethal tools for escaping threats. The answer depends almost entirely on how you like to play the game, and there’s no wrong choice as long as you pick tools that match your routine.
Non-lethal weapons are perfect if you prefer exploring and story progress over base building and hunting. They have minimal impact on in-game fauna populations, so you won’t accidentally wipe out local food sources near your base, and they use far fewer rare resources like crystalline sulfur. The stasis rifle and repulsion cannon combo is the most popular non-lethal loadout, and it works for 99% of encounters even in late-game deep sea areas.
Lethal weapons are the better pick if you’re building a permanent base in a high-threat area, or if you want to hunt leviathans for rare crafting drops. The Prawn Suit Drill Arm + Plasma Cannon combo is the go-to lethal loadout for experienced players, as it can take down even the largest leviathan in under a minute if you aim for weak points. Just note that killing too many creatures in a small area can spawn more aggressive variants over time, so you’ll want to clear threats far from your main base if possible.
If you’re playing on hard mode, you’ll want to carry at least one lethal weapon for exploration below 800m. Most deep-sea threats are too fast to outswim, and a stasis rifle only buys you a few seconds of escape time if you’re caught far from your seatruck.
Weapon Upgrades Worth Spending Rare Resources On
Upgrading every weapon you own is a waste of rare resources, especially if you only use 2 or 3 tools regularly. The three upgrades below give you the highest return on investment, and they’re all worth prioritizing before you start exploring late-game high-risk areas.
- Stasis Rifle Duration Upgrade: Increases freeze time by 70% for leviathan class creatures, letting you escape even surprise encounters without taking any damage. It only costs 2 crystalline sulfur and 1 wiring kit, so it's one of the cheapest high-impact upgrades you can get. It also extends freeze time for medium threats to 20 seconds, giving you plenty of time to harvest samples or grab loot without being attacked.
- Thermal Knife Fire Damage Upgrade: Adds 15 points of ongoing fire damage to every hit, which takes down medium hostiles like snow stalkers or ice worms 3x faster than the base model. It also lets you harvest rare organ samples from dead creatures without extra processing tools, saving you inventory space on long runs. You can find its blueprint in wreckage in the East Arctic area.
- Prawn Suit Plasma Cannon Ammo Efficiency Upgrade: Cuts ammo usage by 50%, so you don't have to carry stacks of ammo canisters on long deep-sea runs. It's a must-have if you regularly explore below 1000m, where reloading in the middle of a fight can get you killed. It also reduces recoil, making it easier to hit leviathan weak points while moving.
Skip the dart pistol toxic upgrade entirely. It uses rare neurotoxin samples that are better saved for advanced water filtration upgrades, and the damage over time is too slow to stop most fast-moving threats. You’re far better off spending those resources on upgrades for your core weapons.
Common Weapon Mistakes That Will Get You Killed
Even with the best weapons and upgrades, small mistakes can turn a routine exploration run into a frustrating death. I’ve made all of these mistakes at least once, so you don’t have to learn the hard way.
The first mistake is carrying only one type of weapon. If your stasis rifle runs out of battery mid-fight, you have no backup to defend yourself. Always carry at least one melee weapon and one ranged tool, even if you’re only going on a short resource run. It takes almost no inventory space, and it will save you more times than you can count.
The second mistake is forgetting to recharge weapons before you leave your base. I can’t tell you how many times I died early on because I left my base with a 10% charged stasis rifle and ran into a shadow leviathan 20 minutes later. Get into the habit of checking all your tool charge levels before you head out, and keep a spare stack of batteries in your inventory for long runs.
The third mistake is using the wrong weapon for the threat. Don’t waste stasis rifle charges on small aggressive fish, just swat them with your knife. Save the big guns for leviathans and ice worms, where their impact actually matters. Also, always store a spare weapon in your drop pod or seatruck so if you die and lose your inventory, you don’t have to start from scratch with no way to defend yourself.
At the end of the day, the best loadout is the one that fits how you play Subnautica 2. You don't need to collect every single weapon available to stay safe, just pick the 2 or 3 that fit your routine, upgrade them properly, and you'll be able to explore even the deepest, most dangerous parts of the map without fear. Taking the time to test and get comfortable with your Subnautica 2 weapons will not only save you from dozens of frustrating deaths, it'll also let you focus on the parts of the game that make it so fun: uncovering secrets, building cool bases, and exploring the beautiful alien world around you.
