While they were exploring the tomb of Roselia, a lot of things had happened.
The war had gotten worse!
The creatures of hell, for some reason, had gotten more aggressive.
Hell's paradise, a spatial rift that connected the realm of the living to the hell realm, had started appearing in massive numbers all around the planets owned by the federation.
The federation dispatched all of its soldiers and every top-notch expert to go to different planets and close Hell's paradise before they could stabilize.
Once stabilized, the creatures of hell could step into their planet.
As they liked to prey on demi-humans, aliens, and humans alike, irrespective of their color, handsomeness, or horror, it was easy for any soldier to calculate that the damage would be huge if they failed to close one within the estimated time that it would take for it to stabilize.
