The scientist's experiments went awry, and the Underground became a battleground. The humans, fearing the monsters, tried to eliminate them. The monsters, defending themselves, fought back. And so, the eternal conflict began.

You're referring to Undertale, the critically acclaimed role-playing game developed by Toby Fox!

You've always wondered what lies beyond the surface of the human world, right? Well, in the world of Undertale, there's an entire realm beneath our feet, teeming with life. The Underground, as it's known, is home to a diverse array of monsters, each with their own unique abilities and personalities.

As you journey through the Underground, you encounter various monsters, some friendly, others not so much. You begin to unravel the mysteries of this subterranean world and the events that led to the current state of affairs.

The choices you make will determine the fate of the Underground and its inhabitants. The story of Undertale is full of twists and turns, and your decisions will lead to one of several possible endings.

Sans, the laid-back skeleton, and Papyrus, his enthusiastic brother, were once part of a group of monsters who tried to make contact with humans. They built a barrier, known as the "RUINS," to prevent humans from entering the Underground, but some humans, like a certain scientist, were determined to explore this new world.