Prologue

As the survivors looked on in awe at the knights in their armor and mages wielding ancient weapons, they couldn't help but feel a glimmer of hope amidst the chaos that had taken over the world. These newcomers spoke a different language, but they were able to communicate with the help of a mysterious device that beamed with light.

It was a stark contrast to the world as it was 100 years ago. Back then, life was much simpler. Children were born and raised by their parents, and they would eventually attend school to learn basic subjects like math, science, and communication skills. As they grew older, they would receive a more advanced education, with some excelling in certain subjects while others struggled.

Once they reached their teenage years, most were filled with uneasiness and concern about their future. They saw their friends either excel or fall behind, and they had to make the difficult decision of what path to take in life. Eventually, they would enter the working world and become independent, trying to earn a living for themselves.

They would often decide to marry and start a family, raising their children through the same cycle. While it may have sounded boring, the reality was that no two lives were exactly the same. Even if someone attempted to mimic another's life, it would inevitably end in failure.

But all of that had changed when something other than the ordinary appeared one day. Dimensional gates, or simply "gates," started appearing all over the world, and out of these gates came monsters. These gates were black, ominous portals that appeared out of nowhere, and the monsters came out of them, wreaking havoc everywhere they went.

Killing the monsters with regular guns was initially possible, but as bigger and stronger monsters started emerging from the gates, guns became useless as bullets couldn't penetrate their skin. Even heavy weaponry like atomic nuclear bombs proved to be ineffective since the evolved monsters had high regeneration abilities, so killing only a few monsters through a direct hit was the best these weapons could do. However, the aftermath of those bombs caused more harm to humanity than the monsters themselves, so there was no choice but to run.

At this rate, humanity was walking towards its doom until a group of people emerged from a dimensional gate. One of them was a male wearing full plate armor, with a helmet covering his face and a sword at his side. He emitted a strong and imposing presence.

Another one was also heavily armored, but in a different way than the first one. It was thicker and bulkier armor, with a shield at their side that seemed almost as tall as they were.

Next to them was a female who seemed garbed in a long robe with intricate symbols and runes embroidered on it, giving off an air of mystery and arcane knowledge. They carried a staff or wand that glowed with an otherworldly energy, and a book of spells might be seen at their side. Their physical appearance was slender, perhaps frail, yet exuded a powerful presence.

And lastly, a man with attire consisting of a fitted tunic or vest, complemented by a pair of leggings or pants. He carried a tall bow made of a lightweight yet durable material and a quiver of arrows strapped to his back or hip. His physical build was lean and graceful, with long muscles indicating his nimble movements.

To all the survivors who were watching from afar, they thought the group was crazy for dressing up in strange armor and brandishing what appeared to be medieval weapons. Staying in the open instead of hiding from the monsters was like wishing for death. After all, the most advanced weaponry couldn't even harm those monsters, so what could those crude weapons do?

But as the group began to fight back against the monsters, the survivors were astounded by what they saw. The swords engulfed in a blue flame-like aura cut through the monsters like butter. The bows sent arrows flying with such force that they could pierce through even the thickest hide. The metallic truck-like machine proved to be an unstoppable force, and the woman in the robe stood behind the front lines, holding her staff at the ready. She chanted incantations, and magical barriers appeared to protect her allies from the monsters' attacks.

The survivors, who were in shock at the absurdity of the situation, realized that a group of four people had wiped out a wave of monsters in a way that clearly exceeded human capabilities. Armies equipped with the most advanced weapons couldn't even stand a chance against these skilled warriors who had been trained to fight against the monsters, as evidenced by their coordination and synchronization. For the first time in a long time, the survivors felt a glimmer of hope that perhaps they could survive this nightmare.