In the year 2068, physicist Haru Hasegawa successfully achieved inter-dimensional travel, marking a significant turning point for humanity.

On May 13th, Hasegawa publicly announced this groundbreaking achievement and organized an immediate expedition. Noboru Suzuki and Izumi Tanaka were chosen as the lead explorers, entrusted with venturing through the portal to explore other habitable worlds.

The entire world watched in awe as the expedition commenced, with the two explorers entering the portal precisely at 8:00 PM. However, what followed was a catastrophic event...

Minutes after the explorers lost signal from home base, an overwhelming and unprecedented pressure engulfed the atmosphere. Unidentified creatures emerged from the portal, flooding Earth in massive numbers, causing chaos and destruction. Humanity was helpless as these monsters swiftly conquered every nation, subduing mankind completely.

The world descended into despair, with the global population decreasing by 50% in a matter of hours. As days turned into weeks, weeks into months, and months into years, the year 2078 arrived, marking a decade of relentless warfare. Despite their best efforts, mankind was on the brink of defeat. However, a glimmer of hope emerged as a discovery was made, potentially altering the course of this catastrophic conflict.

The portal's activation brought about a profound transformation on Earth, saturating it with a potent energy known as 'New Energy.' This phenomenon triggered genetic changes in humans, granting them the ability to manipulate Kinetic Energy.

With this newfound power, humans gained a formidable advantage in warfare, honing and harnessing their abilities to defend themselves. Eventually, the war reached its conclusion as the most powerful Kinetic Energy users successfully repelled the enemy and sealed the portal, securing a hard earned victory.

However, war never truly ends...