In an effort to keep gamers at home during the on-going COVID-19 pandemic, Sony announced that for the second month in a row, a slew of video games will be made available for free as part of its Play at Home 2021 initiative. The big game is, of course, Horizon Zero Dawn, the game where you fight robot dinosaurs (basically) with a bow and arrow. But along with this game, that still merits your time, there are nine indie games also being made available and one of these you should absolutely take the time to play. That game is, of course, Subnautica.

In Subnautica, a deep-space vessel called the Aurora has crashed landed on an alien planted dominated by uncharted and diverse oceans and you, the player, are the sole survivor. The objective of the game is simple and familiar to anyone who has played a survival game before: gather enough resources to get off the planet while also discovering just what happened on this watery rock. There is a mystery to solve here and it gets pretty wild so I won’t spoil it. But the joy of the game really comes in its minute-to-minute gameplay. To compare this to the wide variety of survival games on the market would be a disservice to this game. Too often, games have you punching rocks and building forts while keeping track of your hunger and thirst meters. And those elements are part of the gameplay loop. But the first-person view of exploring the unknown is both awe-inspiring and straight-up terrifying.

We know very little about our own oceans, less so than the planets in our solar system. In fact, around 80% of the oceans on Earth remain unmapped. So to take a submarine and go and explore a totally alien planet that consists largely of oceans is even scarier. Subnautica isn’t a horror game, but taking your tiny sub along the ocean floor and suddenly, the floor disappears into a sudden drop into the black unknown, where giant leviathans will try to eat you and the wails of unknown creatures pierce through the darkness, definitely gets the heartbeat pumping. That fear of the unknown is what makes this game so great and knowing that anything could be out there trying to get you. Suddenly, the shark-infested shallows of the starter zone don’t seem as bad. But the game oozes with imagination. From the eerie kelp forests to the grassy plateaus, the blood kelp zone and the mushroom forest. The regions are so imaginative and unique, literally unlike anything you’ve seen before but also, with a sense of inspiration from our own oceans.

But what will you find in the deep blue sea? You can scan items from the crash to recreate them with your 3D printer in order to build gear and a habitat. But you may also discover alien vents and the promise of a bigger mystery that lies ahead. There are no missions or traditional quests, so it’s up to you (or the help of a Subnautica wiki) to get yourself to the endgame. That said, when you do find something of note, the game will nudge you in the right direction and clues to other landing pods can be found and tracked as well. So you’re not completely in the dark but the game isn’t holding your hand either.

At first, you have nothing at all, but before long, you’ll be able to build some flippers from your escape pod. From there, it’s up to you to build a habitat, a sub, diving gear while also looking for mods to boost the stats of some of your gear. You won’t be able to descend as deep unless you have one of these mods for your sub, for instance, or have an increased pressure resistance. But that just encourages you to explore and find these things, which may be lying on the seafloor, or perhaps inside a piece of the broken ship or who knows where else. Knowing where to lay down your bases is also crucial in Subnautica. Do you stay close to a safer zone, or risk more dangerous grounds to set up base with the promise of better resources in the vicinity? Get enough resources and you can easily set up multiple bases around the map.

The sound design in Subnautica though, oh my. The haunting groans from the peaceful leviathans echo through the ocean and the screams of something more sinister coming from who knows where is enough to send chills through your body and make you reconsider ever going into the ocean for real. The music definitely sets a tone, from a relaxing ambient tune in a more pleasant biome, like your starting area, but when the terror comes in, the tempo and tone definitely change to reflect that.

The fact that this game is coming out for free in April for PlayStation users is wonderful news. I’ve already conquered the deep but I absolutely encourage you to pick up Subnautica if you can. The fact that it’s free for PlayStation owners means you have no excuse for missing out on this gem of a game.