Long ago, two races ruled over Earth:

MONSTERS and

HUMANS

One day, war broke out between the two races.

After a long battle, the humans were victorious.

They sealed the monsters underground with a magic spell.

Many years later...

MT. EBOTT

201X

Prince Asriel, having absorbed a human soul, crossed the barrier and never returned.

Since then, the monsters have learned their lesson. Here, only battle is respected.
#soboldcrusher