Void/Black terrain?

I recently played a map called Space Diplomacy. Everyone starts off on little islands, and when you get a flying unit, you can venture off it. The thing is though, is that it actually looked like space (minus the stars i guess). It was just black, no shadows casted, no visible terrain, nothing. I tried to see how this was done, but couldn't get a hold of the map maker, and the map was protected. This would be perfect for a intro to a map i'm makin (it starts off in space, go figure), so i'm wondering how this is possible.

(Just a side note, for those who say I could just import a black texture and use that as terrain, I don't believe that is the solution. When trying to unload units, it wouldn't let me offload them on the space, meaning that it wasn't just black terrain)

It was probably just the boundary feature in the terrain editor,

It is a tile from outland, called abyss. You can get it into your map by going to advanced->modify tileset->use custom tileset.

Muchos gracias ClosecI, I would of never thought it was a tile already in Wc3. Thx lots

Yeah he's right ignore what I said.

something else u can do:
make deep water, and make water tinting black. Be sure to set the water waves on cliff and rolling shore off.