This guide contains minor spoilers towards areas and creatures in the game, I do not advise reading the below if you do not want your in-game experienced to be spoiled or impaired if you have not yet played Subnautica.
The Reaper Leviathan Overview
The Reaper Leviathan
A carnivorous, aggressive leviathan-class life form of fauna that inhabits multiple diverse regions on planet 4546b.
It's appearance consists of a long white and red-coloured snake-like body with 4 large, red mandibles on it's face and a large, red and flat horn on the top of it's head, which it would've used to fight when in conflict with other creatures, or it's prey.
Data Bank Entry
Leviathan class species are vast organisms at the top of their respective food chains. This species is a streamlined hunter, with highly developed senses.
This leviathan is capable of locking prey in place with four powerful mandibles and drawing it within reach of its jaws. Simulated pressure exceeds Seamoth crush resistance.
The deep roar emitted by the reaper at regular intervals is effectively sonar - if you can hear it, the reaper can see you.
The scanned specimen measured 55m long. Observed circling its prey and attacking from behind. This creature is almost all muscle. Very little brain. No sense of morality. Just muscle, synapses, and teeth.
Motivational note: Congratulations on getting close enough to scan it and living to see the results!
Assessment: Extreme threat - Avoid in all circumstances
Habitual preferences will usually stand at large open areas in the ocean, typically in specific biomes such as:
- The Crash Zone
- The Dunes
- The Mountain
The Crash Zone was originally likely an empty, more dead-looking counterpart of the Grassy Plateau biome, but became even more dead when the aurora ship crashed into it as the crash likely killed a a lot of lifeforms in the area on impact. The crash zone's fauna consists of merely Sand Sharks and Stalkers, but mostly Reapers that prowl the area for smaller lifeforms to snack on. What makes the Crash Zone especially dangerous is the dirty and misty fog of the water, likely caused by the crash of the aurora as it's impact shook sand from the ocean seabed everywhere; despite the fact that this isn't a problem at all for Reapers because even though they are blind as bats, they still use echo-location with their roars.
The Dunes biome is more or less what it sounds like, it's a nice looking biome full of sand dunes that goes to deep depths, having most of it's seabed land at 300m deep. Like the Crash Zone, lots of Sand Sharks and Stalkers live in this biome, however also like the Crash Zone, it is dominated by lots of Reaper Leviathans that constantly fight over territory. What makes the Dunes biome so uniquely dangerous is not only the fact that reapers can hide behind the towering sand dunes, but the fact that the deeper you go, the darker it gets, and this is dangerous because if a Reaper were to spot you, you'd better be on your toes because you won't see it's shadow until the last second.
The Mountains biome is also more or less what it sounds like, a biome that consists of sharp, pointy parts of rocky landscape that shape it like a miniature mountain area, but it more or less has it's name because the Mountain Island is at the edge of the biome. This biome can also get dark as you go deeper, but coming from my experience, it isn't as stressful as the Dunes biome can be, seeing as the Reaper Leviathans that inhabit it are spread out a lot more in comparison to the other two biomes they inhabit, but can still be as unsuspecting to be right behind you.
Encountering A Reaper Leviathan
Most players often have their first encounter with a Reaper Leviathan at the back and / or front of the aurora during the day, seeing as there are quite a few that patrol around the crashed ship, however if you were unlucky as me on my first time, I encountered it in the dead of night, unsuspecting that the large creature making those roars would be attracted to my flashlight as I swum around the back of the ship.
In the occurrence of encountering a Reaper Leviathan when under-equipped and not in any Alterra-brand submersibles, ensure that you immediately swim a safe enough distance away from the reaper while maintaining keeping watch of the creature, if in an event where the leviathan noticeably begins to pursue you, break open an Alterra-issue saftey flare you grabbed from your lifepod and throw it towards the creature from a safe distance away, do not stop facing the leviathan until you are a safe distance away and it has stopped following you.
But in all seriousness, if you would be in front of a Reaper and have no equipment like a Stasis Rifle or Repulsion Cannon, then just swim away at all costs to avoid dying or losing stuff, and believe me, not even a knife on its own will help you in such a situation, same concept applies if you were in an Alterra-brand submersible.
To Kill A Reaper Leviathan
Now onto the fun part, killing a Reaper Leviathan.
From all my experience in fighting, running away from and killing Reapers in this game, is that a Stasis Rifle and a Repulsion Cannon are key, but first allow me to go through all areas and techniques of fighting a Reaper Leviathan - if you're up for the challenge that is.
Bare Knuckle Fighting
This is the area of where you want to be the hard-man, tougher than Marguerit Maida, the Charles Bronson of the ocean; or as I like to call it - a suicidal moron, because you are guaranteed to be killed by the reaper or run out of oxygen trying no matter if you've got a reinforced dive suit or an upgraded oxygen tank. I don't even need to go into detail, just try it for yourself and you'll see why it's practically impossible.
Down To Business
This is the area of being well-equipped and wanting to take care of another nuisance in the ocean. My advice for this would be to equip yourself with the Stasis Rifle and / or Repulsion Cannon and a knife and I'll tell you why:
The Stasis Rifle freezes objects in a bubble that forms from the projectile launched from the rifle itself, this bubble varies in size the more you hold in the fire button, meaning when you hold it in for the maximum duration of 5 seconds, it will release a large bubble that will freeze the leviathan once it touches it and will last for the duration of about 30 seconds before it quickly shrinks and disappears, prompting you to charge and launch the rifle once more.
The Repulsion Cannon is an upgraded variant of the Propulsion Cannon where instead of being able to pick up and launch objects with the device (quite literally the Gravity Gun from Half-Life 2), you can instead launch a blunt energetic force towards anything in a 10 meter point in front of you, this is usually very handy in an event of should the reaper escaping the stasis bubble, you can fire the Repulsion Cannon at it and it will stun the creature for about 5 seconds, giving you enough time to fire the stasis rifle at it again and freeze it once more where you can keep on slicing at the reaper with your knife until it's dead.
Note: it is best advised to bring a couple of spare batteries with you, should you take on more than one Reaper.
This is the area of bringing a Seamoth to a submersible fight. Usually when you encounter a Reaper in your Seamoth, your first indication is to flee immediately and pray it doesn't chase after you and grab your Seamoth, but we're not staying in our base and never going back there again, not today, oh no no; once you're back at your base I want you to build a Moonpool and Vehicle Upgrade Console if you haven't already (blueprints can be found in deep biomes) and slap the Hull Upgrade, Perimeter Defence System and either the Vortex and / or Gas Torpedo upgrades on your Seamoth, allow me to explain these if you don't know:
The Hull Upgrade for your Seamoth increases it's resistance to damage all around, this is essential if you want your Seamoth to last longer should it be grabbed multiple times by a Reaper.
The Perimeter Defence System upgrade releases a shock wave of electricity from your Seamoth after you activate the system by selecting it and pressing, or you can release a much larger shock wave by holding in the fire button, this is most effective to shock the reaper and make it retaliate for a short time span, before the reaper eventually comes back for more.
The Torpedo upgrades allow your Seamoth to fire torpedoes out of the storage system, these torpedoes come in two different variants, the Vortex torpedoes and the Gas torpedoes. The Vortex torpedoes release a magic whirl pool where they explode which drags anything in it's range and spins it around before releasing it at a high speed, this won't as much kill the Reaper but it's a really fun way to troll it. Now I want you to completely ditch the idea of the Gas torpedoes because there has been an unresolved bug in the game for a while that makes the Gas torpedoes do little to no damage to anything, prompting it useless to use against Reapers. Stick to the Vortex torpedoes or use the actual Gas Pods from the Gasopods (yes, you can pick those up) to kill the reaper by dropping them in front of it and letting them explode.
This is the area of using your megalomaniac feelings and using your Prawn Suit to kill a Reaper. The same concept applies to the Prawn Suit with the Hull Upgrades and Torpedoes, but with the Prawn Suit you also have the exclusive upgrades like the Drill Arm and the Grappling Arm.
However I want you to go and throw the idea of using the Drill Arm out of the window because as much as I thought this did damage, it does quite less than punching with the normal Prawn Suit arms would. That being said, I want you to slap the Hull Upgrade and the Grappling Arm onto your Prawn Suit, the default Prawn Suit arm will be your fist of iron when it comes to punching the Reaper.
The Grappling arm will be your main point of killing the Reaper, as this upgrade is pretty self-explanatory, it shoots a grapple which pulls the Prawn Suit onto the grappling point, use this to grapple onto the Reaper while it moves, with this, you can punch it to death, or die trying and go out as a hardcore Reaper grappler.
Unfortunately the Prawn Suit doesn't have the Alterra-Brand Perimeter Defence System compatibility like the Seamoth does, so you'll really just have to wait until the Reaper lets go of your Prawn Suit and quickly repair it, or just be a die-hard and keep fighting it until your suit breaks.
As for the Cyclops, there isn't much you can do with this in order to fully fight a Reaper with it. Ramming into it on full speed is fun enough and will do a bit of damage to the Reaper, however it also damages the Cyclops in the process, so only do this if you have the Cyclops Shield Generator upgrade and want to fully disrespect the Reaper.
Extra Info and Facts
There's lots of extra info surrounding the Reaper, some of it that was either cut or changed in the game's long development:
- The Reaper's red coloured areas of it's body and it's eyes used to be bioluminescent and glowed in the dark, however this was changed in the update for the Reaper's model in late 2017, likely because the developers wanted to make it more horrifying than it already was.
- The Reaper was originally meant to take the role of the Biters, a small pesky creature, however the developers realised it's true potential to be a large-scale leviathan.
- Reaper Leviathan skeletons can be found in the Lava Zones, this was due to the fact that Sea Dragons would supposedly come up to the surface occasionally and drag the Reapers down to snack on, however this intertwines with the fact that the large corridor for the Inactive Lava Zone that went directly up to the surface at the front of the Aurora ship was sealed off before the game's 1.0 release, making this fact not make as much sense as it should.
- There was once a bug that existed early development where there would be a reaper spawn in the safe shallows, this was supposedly a random bug that was fixed in late 2015, yet still scared the ♥♥♥ out of others who wouldn't have thought a Reaper would be in the safe shallows.
- The Reaper was originally planned to be in the game's sequel Subnautica: Below Zero, but the concept was quickly changed and it was replaced with the Chelicerate Leviathan, despite the fact that you were able to spawn the Reaper in earlier game versions of Below Zero with console commands.