```
How is that possible?
Every person on the scene thought so, except for Roland, whose expression was grave.
Leaving aside why increasing the oxygen concentration would freeze the world, under the ecological cycle—the regulation between animals and plants—the atmospheric oxygen content always maintains a relatively stable state. Even if someone developed a way to promote plant growth, the rate of animal growth would also automatically increase, offsetting the rise in oxygen concentration caused by plant growth. This is basic natural science common knowledge that even elementary school students in Alfheim are aware of.
