Subnautica and its sequel Below Zero are two fascinating twists on the usual survival game. Combining alien worlds and a vast underwater setting, they feature a variety of fascinating and fearsome fauna.

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Among these many creatures are the games' Leviathan-class organisms. Bringing the fearsome myths of old to life, both games host a variety of Leviathans in their waters, some more dangerous than others. And so, here's every Leviathan in Subnautica and Below Zero, and where to find them.

11 Sea Treader

Sea Treader Leviathan in-game PDA Art

Sea Treaders are among the more passive Leviathans, and will not actively attack players unless provoked (usually done by getting closely in front of them). They are a tri-pedal bottom feeder, and are primarily located in the aptly-named Sea Treader Path, a small biome situated between the larger Grand Reef and Dunes.

Though somewhat difficult to locate, these Leviathans can be of value to players. Their feces can act as biofuel survivors can use to power their home bases. And their titular "treading" along the sea floor churns up shale outcrops, a perfect source for rarer materials and resources.

10 Reefback

Reefback Leviathan pod Art

Reefbacks are another passive Leviathan of the original Subnautica. They can be found idly floating in various surface-level biomes, and are especially common in the Grassy Plateaus, Mushroom Forest, and Bulb Zone.

Though not hostile themselves, their titular "reef back" may host the dangerous Tiger Plant, which can hurl projectiles at players. Aside from the floral pest, Reefbacks are also hosts to numerous other underwater flora, alongside barnacle nodes, which hold valuable resources like Copper or Silver.

9 Reaper

A Reaper Leviathan attacking a Seamoth

Reapers are usually the first hostile Leviathans that players will encounter. This predator commonly stalks along the Crash Zone, with one guarding the front of the Aurora and several others throughout. They're also scattered about the Mountains and Dunes biomes, making them two of the more dangerous locations in-game.

The bite of a Reaper can do 80 damage to a player, and instantly kill if already they're below that health. Reapers can also deal 40-60% damage to Seamoths and 16-25% to Prawn Suits, though they fortunately can't harm a Cyclops Submarine. Still, players best beware of this titanic predator when exploring.

8 Ghost

Ghost Leviathan PDA entry art

Ghost Leviathans are the second most common of the predatory giants in Subnautica. These translucent Leviathans can be found as adults in the Blood Kelp and Grand Reef biomes, with their Juveniles stalking the Lost River. Should curious survivors deviate too far from the map, three more adults will also spawn in the Crater Edge and chase players down to death, or back to the safety of the known world.

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Though the Juveniles do less damage than the adults, these creatures still pose a serious threats to players, their Seamoths, and their Prawnsuits. However, these are also the first Leviathans capable of attacking the Cyclops, doing between 220-250 damage with each bite. So players should engage in caution when approaching these Leviathans.

7 Sea Dragon

Sea Dragon Concept art, next to player for scale

Sea Dragons are the largest hostile predator of Subnautica, even preying upon fellow Leviathans like the Reaper. They can utilize a variety of methods to attack players and their vehicles, from biting, using their forelegs, breathing small fireballs, or hurling out a giant fireball. And should players seek to unravel the mysteries of planet 4546b, they'll have to contend with these titanic terrors, as their home biomes, the Inactive Lava Zone and Lava Lakes, are also the location of valuable plot points.

6 Sea Emperor

Sea Emperor resting animation, within the Primary Containment Facility

The Sea Emperor is the last Leviathan of Subnautica, is tied to the major plot of the game, and fortunately for players, is a gentle giant. Before completing the plot, there will only be one Emperor in-game, located inside the Primary Containment Facility inside the Lava Lakes. After completing the plot, there will be five hatchling Emperors released into several biomes of the world. And should players choose to linger on the planet a little while longer, they'll eventually grow into Juveniles. Not as big as their parent, but certainly a sight to see.

5 Glow Whale

Glow Whale concept art

The first of Below Zero's Leviathans, the Glow Whale is one of two passive titans found about the arctic waters. They're extremely similar to many of Earth's own whales in behavior and appearance, albeit with an alien flair (though whether they're mammalian or not has yet to be determined), and Robin can interact with them in various ways.

These gentle giants can be found in the iceberg-ridden East Arctic and Lily Pad Island biomes. They generally have no purpose to surviving, too big to be food or recycled into biofuel. But they're certainly a majestic and familiar sight to see in these alien waters.

4 Vent Garden

A Mature Vent Garden in the Tree Spires Biome, alongside a Tree Spire and several Tornado Plants

Vent Gardens are the other passive Leviathans of Below Zero. They're primarily located in the Tree Spires biome, though a few Juveniles can be found around the Purple Vents. These passive Leviathans look somewhat jellyfish-esque in appearance, though they're distinct in their tethering to the sea floor.

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Unlike most other Leviathans of the game, Vent Gardens harbor a valuable resource. As their name suggests, these animals also act as living gardens, home to a variety of flora, namely the Spiral Plant. And this specific plant is needed for crafting a variety of important materials, be it for survival or the plot.

3 Chelicerate

A Chelicerate Leviathan mid-attack animation

The Chelicerate is the first major aggressive Leviathan of Sector Zero that players will probably encounter. They appear semi-crustacean in form, and can be found in a several biomes: the East Arctic, Purple Vents, and Tree Spires—alongside a variant that patrols the Void, the de facto end of the map.

A bite from this fish will deal 75 damage to players, and instantly kill if they're already under that health. It can also deal damage to Sea Trucks and Prawn Suits, varying from 15-30% and 21-33% in damage, respectively (depending on defensive upgrades). So when exploring the world, best be sure to give these beasts a wide berth.

2 Ice Worm

An Ice Worm in the Arctic Spires biome, mid-scouting animation

Ice Worms are another aggressive Leviathan of Below Zero. They're also the most unique among both games, as they're the only living Leviathan that patrols on land. Indeed, these terrifying titans are located solely in the Arctic Spires biome of the map. And unfortunately for any players interested in the plot, they'll have to traverse this region for several important artifacts.

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These creatures appear as a gigantic, alien-esque bobbit worms that will attack Robin, the Snowfox bike, and even native Snow Stalkers. But players can also use Thumpers as a distraction to these beasts, and safely navigate the arctic landscape. So players should be sure to stock up before they go traversing above the ice.

1 Shadow

A Shadow Leviathan in the Fabricator Caverns, in mid-charge animation

The Shadow Leviathan is the last aggressive giant of Below Zero. Several of these titans can be found in the deepest biomes of Sector Zero: the Crystal Caves and Fabricator Caverns. And much like the Arctic Spires, these regions are necessary for players to explore, should they want to progress the game's plot.

Much like the Chelicerate, it can deal 75 damage to players and insta-kill if at lower health. But these beasts can deal even more damage to the Sea Truck and Prawn Suit than their top-side counterparts. An attack can average 20-35% and 33-42% in damage for each respective vehicles, meaning if players aren't careful, they can quickly lose their transports (and any resources within). So players best beware this behemoth of a fish.

Next: Subnautica: How To Find The Blue Tablet