Mantlenaut
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Monsters and legends
Every legend in Mantlenaut grows out of something real in our own world, then gets a lot bigger. Thirty-one are in the game today, each fought its own way, and there are more on the way.
Thirty-one legends are waiting for you in the alpha, from the sea floor and the deep rock to other worlds. Each one is fought its own way.
In the gameThe Kraken's secret
The Kraken was never the real boss. A parasite in its head steers it, and when the Kraken dies it crawls out and swims for a new body: a whale or a greyfin, which it rides stronger and angrier. When that host dies it leaps free. Hit it then.
Real: The tongue-eating louse eats a fish's tongue, then lives in its mouth and works as the tongue.
In the gameBoss · hot sands and ash
Forty metres of basalt rings and magma seams that swims through the ground under the deserts and ash plains. The rumble grows, then it breaks the surface in an arc, rears up, opens its four-petal maw and strikes. Only what is out of the ground can be hurt.
Real: Real worms tunnel through soil by swallowing it; this one swallows rock.
In the gameBoss · the deep rock
A crystal eel that swims through solid rock, turning it to water behind it and flooding your tunnels. It can't pass anything built. Line a tunnel with brick, lure it into the air, and strike it stranded.
Real: Piddock clams bore their homes into solid stone.
In the gameBoss · the deep mines
A giant worm that swims through the rock eating ore: your gold vein becomes an empty tunnel. It hears you dig. Drop gold on the floor to draw it out, strike while it gorges, and the treasure in its stomach is yours.
Real: The "devil worm" was found living 1.3 km down a gold mine.
In the gameBoss · the jungle worlds
A spiky seed head ten metres up on three stilts, striding through the purple jungles. It flings hooked burrs that stick to you and slow you, and they drop off and grow into tearing bramble wherever you go - even back home. Wash them off in water. Strike out its seed pods, then hit its head when it stoops to sniff its seeds.
Real: Burdock burrs hook onto fur so well they gave us Velcro.
In the gameBoss · the volcanic worlds
A boulder golem with a furnace for a belly. It spews liquid stone that sets round you in an instant: sealed inside you can't breathe, so break a gap before your air runs out - or a friend must dig you out before it comes back to finish its statue with its chisel. Strike its belly when it cracks open.
Real: The Petrifying Well in Yorkshire turns things left in its water to stone.
In the gameBoss · the forests
The whole wood is one fungus. Cut down too many of its trees and it wakes: glowing trunks burst up out of the ground round you, closing you in, and the roots at their feet lash anyone who stands by them. Chop them and they come again. Only its heart can be hurt: dig down to it under the roots.
Real: An Oregon honey fungus covers more than 1,600 football pitches, and its threads make dead wood glow.
In the gameBoss · the mountains
A horned beast of storm cloud roams the high peaks. Climb near it and the storm comes with it: it calls lightning down on you, and the ground at your feet glows first, so move. Blows mostly pass through its cloud. But a bolt goes to metal: stand a block of iron near and the lightning takes the rod and arcs straight back into it.
Real: Lightning rods have guarded buildings since the 1750s.
In the gameBoss · plains and jungle
A castle of giant ants linked leg to leg. By night it marches across the land eating every tree, leaf and crop it walks over, and a wooden wall is wood. Its walls are solid and they bite. Break a block of wall and more ants rebuild it, unless you stand in the gap. Only its queen, inside, can be killed: siege it like a castle.
Real: Army ants build nests and bridges out of their own bodies.
In the gameBoss · anywhere crops grow
A yellow slime mould that comes for your food. It spreads a film of slime toward your crops, round every wall in its way, until one tendril gets there. Then it pulls back every dead end and slides along the one shortest way to eat. Change your base, cut its vein, and it has to solve it all again. It will never cross salt.
Real: Slime mould solves mazes, and once grew a copy of Tokyo’s railway map between oat flakes.
In the gameBoss · the jungle
A tall fungus rooted in the jungle that takes your animals, pets first. A taken animal climbs to the highest place it can find and bursts, and a tower of spore stalk grows out of it that hurts anyone near and takes more animals. Burn the towers with fire beside them, cure your herd with a broth, then cut the Shepherd down.
Real: The zombie-ant fungus walks an ant up a stem to die high, so its spores rain on the rest.
In the gameBoss · the salt flats
Under a dazzling salt flat a crust-backed crab the size of a house waits for rain. The storm floods the pan and it bursts up to feed. Its salt crust shrugs off blows: go for the eyes, or the belly when it rears after a slam.
Real: Dried lakes burst into life after rare rain: brine shrimp eggs can wait decades.
The seas go deeper, and so do the things in them.
In the gameBoss · the Hadal Rift
It sleeps at the bottom of the Hadal Rift, two hundred metres under the waves. Wake it and it fights in three phases: grabbing, sweeping, inking the water black and pulling you into a whirlpool. It hunts ships too, and snaps a held one in half. Its eyes are the weak spot.
Real: Giant squid really do live in the deep ocean, with eyes the size of dinner plates.
In the gameBoss · the sea floor
A dead whale's skeleton that walks, with billions of bone-eating worms as its muscles. Smash its bones and the worms rebuild them: only the spine, with a red heart glowing in its ribs, can be hurt. Break five bones at once and it collapses. It rises where a whale fell.
Real: Whale falls feed life on the seabed for decades, including worms that eat bone.
In the gameBoss · the deep sea
Far down, a shaft of what looks like sunlight: the way up, you think. It is the lure of an anglerfish the size of a hill, and swimming up to it takes you into its jaws. It finds anyone carrying a light. Strike the lure and it goes dark, and blind.
Real: Anglerfish lures glow with light made by bacteria they farm.
In the gameBoss · the deep sea floor
A glowing spiral net sixty metres long on the deep floor: thousands of bodies, each with one job. Its stingers hang lines that sting and reel you in to its stomachs. Cut its swimmers and it is pinned, cut its lights and it is blind. Cut it through the middle and there are two.
Real: A spiral siphonophore about 45 m long was filmed in a canyon off Western Australia in 2020.
In the gameBoss · the reefs
Something you know swims near you on the reef: a fish, a whale, even your own pet. It keeps a little way off, and nothing warns you. Its tell: it never takes its eyes off you. Come too close and it throws off the shape and bites, then becomes something else. Strike it while it still pretends and the blow lands twice.
Real: The mimic octopus impersonates lionfish, sea snakes and flatfish to fool what hunts it.
In the gameBoss · the deep sea floor
A lake at the bottom of the sea, with a shore of salt: brine so heavy you float on it like a floor. Wrecks lie pickled on its bottom with their treasure. The Warden, a pale pickled eel, lives in it: swim low over its lake and it drags you under. Strike its head to break free, and only when it rises out of the brine.
Real: Brine pools lie on the floor of the Gulf of Mexico, with shores, waves and pickled animals that swam in.
In the gameBoss · the reefs at night
A giant jellyfish that can't die. Beat it and it shrinks back into a baby and hides among a swarm of look-alikes. Find the real one within a minute, by its light beating out of time, or it grows back faster.
Real: The "immortal jellyfish" turns back into a baby and starts its life again.
In the gameBoss · the reefs
Seven blind giant shrimp on the reef that hunt by sound. Swim fast, mine or build near them and they snap: the bubble bursts where you were and smashes blocks. Creep, or throw things into the water to fool them.
Real: Pistol shrimp snap a claw so fast the bubble it makes flashes hotter than the surface of the sun.
In the gameBoss · the open sea
A monster made of water, living in water: blows pass straight through it and it swallows swimmers. Stain it with Kraken ink to hit it, or lure it into a sealed room where it can't heal.
Real: Comb jellies are as clear as glass: you only see them where the light catches their edges.
Dig deep enough and the planet digs back.
ComingBoss · the outer core
It swims in liquid iron, and its swimming makes the planet's magnetic shield. Kill it and compasses spin, radiation storms hit and auroras fill the sky. Maybe calm it instead.
Real: Earth's magnetic field comes from liquid iron moving in its outer core.
Even the land has teeth.
Other planets, other oceans, other hunters.
In the gameBoss · the dead grey moons
A ball of crushed matter so heavy it has its own gravity. Come near and it pulls you in - crouch to dig your boots in - and crushes whoever it reaches. It hurls the boulders that orbit it, and its pull swings them back round at you. Knock them out of the sky to reach its core.
Real: A teaspoon of neutron star weighs about a billion tonnes.
In the gameBoss · ice fields and glass dunes
Every glowing crystal is one of its eyes. Whoever an eye sees, a crystal spike erupts under them - crouch and keep rock between you. Mine its eyes to blind it, and when only a few are left its crystal heart heaves up out of the ground to look for itself.
Real: Brittle stars are covered in tiny crystal lenses: the whole animal is an eye.
In the gameBoss · the ocean worlds' shores
A figure of living quicksilver that nothing can touch - now. But it remembers: ten seconds after you do anything near it, a silver echo of you climbs out of the sea and does it again, and only your echo's blows land. Plan ahead. Four friends, four echoes.
Real: Mercury - quicksilver - is a metal that is liquid, and a perfect mirror.
In the gameBoss · round the pulsars
A wraith of lightning that only exists in the flash of a pulsar's beam. On every beat it lunges or strikes - and only on the beat can it be struck. As it weakens, the beat comes faster.
Real: Pulsars sweep their beams round many times a second, regular as a clock.
In the gameBoss · Phaton, the acid world
A snail the size of a house under a shell of acid-green glass. Its foot sweats acid: the ground dissolves under it and it eats through your walls. It spits acid that eats your suit. Acid is undone by a base: lure it onto limestone, chalk or marble and it fizzes, soft and harmless for ten seconds.
Real: Limestone neutralises acid - it is why limestone country shrugs off acid rain.
In the gameBoss · the lava seas
A black whale that swims in lava where nothing can touch it. It breaches and comes down on whoever is on the shore; beached, its skin cools to glass, and glass breaks. On sunny days it basks and its glassy back gathers the sun into a beam on you: get rock between you.
Real: Lava cools into volcanic glass (obsidian) when it cools fast.
In the gameBoss · every world but home
An eight-legged water bear the size of a ship, plodding over alien worlds and even the airless moons: nothing out there can kill it. It bites and stamps; every quarter of its health lost, it dries into an armoured barrel that shrugs off every blow. Rain, or a lake you lure it into, leaves it soft: then it takes double.
Real: Tardigrades survive open space, boiling and freezing by drying into a "tun"; a drop of water brings them back.
ComingBoss · the gas giant
A ship fight while you collect fuel: a floating diamond jellyfish catches the diamond rain and fires it at your hull. Bring it down for a fortune in diamonds.
Real: It may really rain diamonds deep inside Neptune and Uranus.
Some pictures here are concept art, drawn before the legend was built: the Kraken and the Mantle Wurm pictures are from the game, and the rest become the real thing as we take them. Every legend arrives in the game as a milestone of its own, modelled in Blender, animated and tested. And there may be something out there we haven't told you about.