Need to know how I make neverending ditches in the ground, like in outland maps

In outland maps

I notice that there are areas where there is no ground, its just black endless drop (I presume), its part of the terrain

Do I accomplish this by continuous lowering of the height?

Or is there some other way?

any help is appreciated

Thanks!

There is a terrain type called abyss for outland that is the blackness u see. If you lower the ground level enough it will also create an abyss hole chasm thing.

It's the part of the tileset called Abyss.

Its also the water in outland maps, and changeing the water tinting color to black in the map options will change other tileset's water to this aswell.