Killing monster and resource box

The temperature inside the safe house is rapidly rising. Before long, it feels like a massive oven. Ulva's body seems to be getting cooked.

"Get ready to open the door!" Waldo says in a deep voice, following the system's instructions. Outside, the monsters are actually transformed bodies of past challengers. However, they are much stronger than the survivors.

Typically, regular challengers wouldn't stand a chance against these creatures.

However, the monsters have a fatal weakness—they fear fire. It's difficult to kill them through other means because in the darkness, they are not only exceptionally powerful but also nourished by the mysterious energy floating in the air.

Once injured, they quickly recover, making them nearly impossible to kill unless the opponent is significantly more powerful. Only fire can restrain them, and Waldo happens to possess the ultimate ability [Fire Control].