This is a very good tutorial!
Clone Index is an object variable that counts what “Clone Number” a certain clone is
ex: the 3rd clone is the same as Clone Index = 3
Btw, if you wanted to do this with any x pos, just remember to make the game reset the var to the beginning x pos
Since the original object has Clone Index =1, the first clone has Clone Index = 2, second clone, Clone Index = 3, and so on.