But the Nightmare Plane is not all high-level life.
Like any regular plane, it also has a pyramid ecosystem at the bottom.
There are native creatures below Level 1, unique plants and minerals, and its own operating rules.
Those top-tier beings do not randomly slaughter the low-level life of their plane, just like humans wouldn't deliberately step on every ant in their view.
Yet, this is still a top-tier plane, the pinnacle existence in the whole Endless Plane.
Because of this, the Wizard Plane is extremely cautious about the Nightmare Plane.
No Wizard Organizations would openly organize expeditions to the Nightmare Plane, not because they don't want to, but because they're afraid to.
If the powerful beings of the Nightmare Plane were to notice the Wizard Plane due to unrestrained access, it could bring about an apocalyptic disaster for the Wizard Plane.
Given the current power of the Wizard Plane, it absolutely cannot contend with the Nightmare Plane.
