Missile that can´t shoot up or down cliffs?

[Kabel]

I try to make a projectile that can´t shoot up or down cliffs. It can only shoot at target´s on it´s own ground level and it can´t shoot over water/space etc.

It is a ranged attack from a ground unit that target´s other ground units and deal splash damage to ground in a small radius.

This sounds like the reaver attack, but it is not for a reaver. I don´t need any cargo for 5 missiles etc.

Anyone wanna show me the basic steps and principles so I can figure the rest out?

 

[Dr Super Good]

As there is no such thing as "space" or "water" in StarCraft II, this is impossible directly. You will need to use some other concept line "unpathable" or cliffs to separate areas which you place water graphics or space graphics.

The not shooting up cliffs is done by using a validator to compare the cliff heights.