It feels like you stepped into an oven.

There are no plants or any vegetation, and almost no moisture in the air.

The sunlight, smashing down from the cloudless and weirdly colored sky, is reflected by an endless sea of red and orange sand dunes stretching over the horizon for thousands of kilometers.

Dust devils the size of buildings dance over the hellish landscape.

You're in the early Triassic, hot house Earth 250 million years ago, a few million years after the worst mass extinction in history.

The planet is still suffering from a permanent fever.

Volcanism and the runaway greenhouse effect has transformed the planet into hell.

There's three to five times more CO2 in the air than in the human era.

The formation of the massive supercontinent Pangaea led to the largest desert in history that barely sees any rain.

The gigantic ocean is warm even deep below.

Two superheated currents circulate around the globe, pumping extreme amounts of heat and moisture into the atmosphere.

There's no ice, even at the ponds.

Seems like you're stuck in the center of the desert, isolated by endless ancient landmasses.

One of the most hostile environments Earth has ever produced.

The deserts we know are still full of life, but not this one.

Its core is starved of moisture and the air is bone dry.

Your skin dries out immediately and your lips begin to crack.

The CO2 rich air is easily 50 degrees Celsius and sears your lungs with every labored breath.

The rubber soles of your boots begin to melt.

If you touch the ground, you'll get burns.

Your sweat evaporates before it could cool you and your exposed skin begins to crack within minutes.

Suddenly, it becomes even hotter as a red sandstorm envelops the landscape.

Like thousands of tiny sparks, burning hot sand hits your skin.

You're pressing your machine's buttons at random.

It can't do time travel, but it can still move.

You shoot over some of the mightiest mountains Earth has ever seen.

Eventually, you stop at the shores of the Tethys Sea.

The vast shallow ocean looks more like a swamp among scattered groups of waist-high ferns and spindly stems with tufted foliage.

A few Lystrosaurus feeding on them eye you curiously.

The water is murky and looks sickly and milky.

Colorful mats of bacteria float on the surface like oil slicks.

The air is hot and humid like a steam room.

It's hard to breathe and your sweat can't evaporate and cool you.

Even the water can't give you any relief.

It's as hot as a freshly run bathtub.

This hot ocean can't hold much oxygen, especially in deeper layers.

Bacteria and bivalves are the only species that thrive here.

The waves move almost sluggishly through this thick bacterial soup.

When they break, they leave behind a glistening iridescent film.

Each wave that hits the shore releases a mist that makes your eyes and throat burn, carrying the rotten extension of hydrogen sulfide up from the oxygen-starved depths.

Barely conscious from the heat and smell and CO2, you look at the horizon.

A storm is building unlike any you've ever seen.

The hot ocean feeds it endless energy and with no continents to slow it down, it will dwarf the fiercest hurricanes of your time.

You're doomed.

Your broken time machine jolts and screeches.

Something's happening.

You're near the equator in the Lake Carboniferous, 320 million years ago.

The atmosphere is thick with moisture.

The climate is locked in a never-ending wet super-summer without any other seasons.

Colliding continents are covered by the largest swamps the planet will ever see.

A paradise for plants, growing faster than their dead biomass can decompose.

The ground beneath is a warm, soggy mass of decaying vegetation.

What will be an endless desert in 70 million years is now an endless alien jungle.

A huge variety of life is thriving in this period.

From your perspective, this is not that great.

You're lost in a maze of giant tree-like plants towering over a twisted undergrowth of giant ferns and endless varieties of bizarre and unfamiliar vegetation.

The thick, humid air smells of sweet decay, but breathing makes you dizzy.

Your vision seems too sharp, your thoughts slightly frantic.

The dense plant cover has supercharged the atmosphere with oxygen, 60% higher than in the human era, and your body is trying to cope.

Which is great for the dominant land animals, which have conquered every niche of this majestic garden. You're stuck in the golden age of arthropods.

In this oxygen-rich world, they have evolved to sizes that will never be possible again.

They are innumerable and everywhere.

Armored, cat-sized megarachni crash through the undergrowth, hunting a swarm of panicked roachoids that scatter in all directions.

Above you, a griffon flyer with wings spanning nearly a meter and beating like helicopter blades catches a Palaeodictyoptera mid-flight.

You stumble through the bushes filled with countless crawling creatures as an arthropura the length of a car picks its way through the ferns, moving countless legs in hypnotic waves.

You reach a swampy clearing and stumble into the shallow water, dizzy and terrified as a pulmonoscorpius rips apart its prey, eyeing you with some interest.

Here in the clearing, you can see the sky above the canopy glow shrieking red, intensifying at an alarming pace.

The extreme humidity here creates sudden, violent thunderstorms, and the oxygen-rich atmosphere makes everything dangerously flammable.

Even the wet vegetation can burst into explosive flame with the slightest spark.

Why do all of your trips end in a storm?

Well, at least it will take all the creatures that want to eat you with it.

Your broken time machine jolts back to life.

The world is folding in on itself.

You've woken up in the early Devonian, 400 million years ago.

Most of the planet is covered in shallow seas, while the land is mostly rocky plains and mountains broken by braided rivers and mudflats.

Earth is in a state of transition.

For about 100 million years, life has begun to break down rocks into soil, a soft layer that enables plants to grow and life thrive.

The ozone layer is slowly building up, fed by organisms releasing gases.

Recently, this process has been speeding up.

The land is turning from toxic to semi-habitable.

The sky looks wrong somehow.

The sun blazes harsh and white, barely filtered by the unfamiliar atmosphere.

The air feels thin, with only 15% oxygen compared to today's 21.

Each breath feels shallow and unsatisfying.

You're on the verge of passing out and can only move slowly.

At least it's currently moderately warm and not stormy.

But it's what dominates these lands that makes this world truly alien.

Reaching up to 8 meters into the sky are massive obelisks of fungal prototaxites.

As you walk closer, you notice spores catching the sunlight, drifting through the air like tiny stars.

Your movement disturbs more of them, creating clouds suspended in the thin atmosphere.

They coat your skin with a fine, powdery, itchy film.

You try not to think about how many you're inhaling with every breath in this oxygen-poor air.

The ground feels nothing like soil.

It's mostly rock, partly covered by a thin, slightly springy layer of decomposing matter.

Some shallow water pools reflect the pale alien sky above.

Between the fungal towers, there's a carpet of smaller fungi and a few alien-like primitive plants.

No flowers, no leaves, just strange green stalks and fern-like structures that reach your ankles.

Around you, the fungal towers rise like pale pillars.

Their surface is neither smooth nor rough, but something in between.

They're neither wet nor dry, slightly yielding under your touch.

Small patches of what might be lichen create splashes of muted greens and yellows on their surfaces.

The only animals you can spot are a few insects burrowing into the large mushrooms.

Everything is eerily quiet.

You sit down on a rock.

Is this it?

As the night approaches, the pale sky shifts into sickly purples and greys, bleeding into the darkness.

No animal sounds announce the coming night, just the solemn whisper of the prototaxites creaking in the wind.

Through the thin atmosphere, the stars and the Milky Way illuminate the scenery with unsettling clarity.

The fungal towers loom as pale shapes against the starlit sky, their silhouette seeming even more wrong in the darkness.

You are utterly alone, a time traveler lost in an alien world.

Your time machine sputters.

What now?

Time to start rebuilding civilization.

And while a hammer and saw would come in handy, the single most important tool you'll need is your mind.

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Welcome to the Kurzgesagt lab.

Let's conduct a few stellar experiments.

We'll first add some more mass to this protostar.

More.

A bit more.

Wow, we've just created a blue giant, a star with 10 times the mass of our sun.

Let's now add a couple of million years and see what happens.

A supernova.

Breathtaking.

And look, it leaves behind a black hole.

Fascinating stuff.

Now we record our findings.

Be careful to preserve the sparkle.

It's now time for Duck's final inspection.

This one is always a nail-biter.

He has incredibly high standards.

Lucky for us, our work is scientifically accurate, offers an overview of important astrophysical processes and is a real stunner.

Duck approves.

Looks like it's ready to be shared with the world as a poster.

A very special piece of Kurzgesagt you can take home and touch.

You can get this very special poster along with many other science-y and space-y things created with love and care from our shop.

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