In the distant past, the vast ocean gave birth to countless lives. About 4.5 billion years ago, the nascent oceans were tiny and small, not even the size of today's lakes.

At that time, in the process of gradual cooling and solidification, the outer surface layer of the earth's crust was collided and squeezed by the violent internal movements of the earth, resulting in uneven folds and sometimes even squeezing out, causing earthquakes and volcanic eruptions, and magma and hot gas gushing out. This phenomenon occurs frequently at first, then gradually decreases and eventually stabilizes.

As the earth's crust gradually cools and settles, the earth's surface resembles an apple that has been dried for a long time, full of folds and undulations. Various terrains such as mountains, plains, rivers, and ocean basins have emerged.

For a long time, the sky has been mixed with water vapor and the atmosphere, and dense clouds have shrouded the earth. As the earth's crust cools, the atmosphere gradually cools, and the water vapor gradually gathers into water droplets with tiny dust and volcanic ash as condensation nuclei, and the amount is increasing day by day. Due to the uneven distribution of temperature, violent convection currents formed in the air, producing thunder and lightning, strong winds, torrential rain and flooding, and the rain poured down for a considerable period of time. The floodwaters converged into thousands of rivers and eventually formed huge bodies of water, known as pristine oceans.

About 3.6 billion years ago, tiny primitive cells were born in the primordial oceans, thus starting the course of life on Earth. Over time, a variety of different types of plants and animals have emerged, enriching the planet's biodiversity.

However, in modern times, 71% of the Earth's surface is covered by vast oceans, and human overexploitation has led to less and less habitable land, and the habitats of plants and animals are threatened.

While the fabled 2012 apocalypse didn't happen, it marked a new beginning for sea creatures. The Earth's interior is violently moving, the Earth's crust is shocked and squeezed, and massive earthquakes and volcanic eruptions sweep in, as if history repeats itself. These drastic changes have reshaped the geography of the planet.

Humanity has lost the memory of how to deal with the catastrophe of that time, only knowing that after the catastrophe, 93% of the earth's surface was turned into an ocean, and the global population of more than 6.3 billion people is now less than 100 million.

On less than one-third of the original land area, humans struggle to survive. That catastrophe wiped out thousands of years of scientific and technological progress and civilizational achievements. However, the subsidence of earthquakes and volcanic eruptions did not mean the end of the disaster.

To their horror, people discovered that the two larger landmasses that exist are Antarctica and the Tibetan Plateau, which was once part of Asia. This situation shows that the geography of the planet has changed dramatically, further raising concerns and explorations about the future.

In these two very different environments, one is perennially icy and cold, and the other is a plateau that is steep and difficult to adapt. But now, even without the support of technology, people don't live in these places.

On the remaining islands, no one will go because the ship has been lost and no one dares to venture to find it.

Although the sky still rains deadly with dust and volcanic ash, people are still looking for survival. Homes are gone, the environment is dire, animals and plants are dying in large numbers, and polluted water sources are no longer safe. Without food and water, the weakened human race is dying and fewer and fewer people are surviving.

In order to survive, people have to drink rainwater that has been simply filtered and even dive into polluted oceans to compete with surviving sea creatures for food and space. The abundance of algae in the ocean becomes their main food source.

Year after year, they struggled to survive in harsh conditions, and after drinking clear rainwater, their bodies changed, becoming stronger and able to live in the water for longer.

And the most amazing change is the emergence of new life.

When the first boy with fins and gills was born, the world was shocked. After the birth of the first girl with a human body and a fishtail, it caused even more sensation.

More and more new life is being born with fins, gills, and even fish tails, giving people hope for survival, but also frustration. Life originates from the oceans, where fish appeared 400 million years ago and evolved over hundreds of millions of years to produce a diverse variety of species. And now, humanity is once again heading to the ocean.

The era of mankind is coming to an end......

The newly born generation is called mermaids and is divided into mermaids, the former being female, with a human body and a tail, and the latter being male, with fins and gills.

As time passed, the last human beings disappeared into the long river of history, new civilizations arose, and mermaids settled in new territories. They live in shallow areas of the sea close to land, and no longer rely on the meager resources of the land, but instead seek survival in the sea.

As the mermaid population grows, they begin to set their sights on the deep sea, where there is an endless treasure that will be theirs if they can defeat the creatures of the deep sea.

However, they ignore the fact that sea creatures also evolve, so how can those creatures that have been living on their own strength stop evolving?

On the periphery of the shallow sea area of the New World, there is a fault between the continental shelf and the ocean floor, called the continental slope, which is called the "forbidden ring" by the mermaids. An earthquake decades ago caused the area to subside, creating a cliff that enclosed the entire New World. Inside the cliff is a shallow sea, and beyond the cliff is the underwater world thousands of meters deep.

After the cataclysm, the world pattern changed completely, human beings ceased to exist, and large sea creatures became the overlords of the sea, like the return of ancient times. Extinct creatures have reappeared due to atavism, and they are fierce and powerful, far surpassing the merman. However, these large creatures are limited by the deep-sea environment and cannot enter the shallow sea, which allows the mermaids to reproduce and settle down.

This "trap ring" destroys the old world and provides protection for the mermaids of the new world, whether it is a blessing or a curse, no one can say.

Now, on the edge of the "Forbidden Ring", a team of mermaids floats neatly in the water, harpoons on their backs, ready to go. Their mission is to explore the waters outside the forbidden ring and find more seabed resources.

"Let's go."