Instantiating C#??

for(int x = 0; x < Cubes.Length; x++)
		{
			for(int y = 0; y < Cubes.Length; y++)
			{
				for(int z = 0; z < Cubes.Length; z++)
				{
					Instantiate(Cube,new Vector3((float)x,(float)y,(float)z),Quaternion.identity);
				}	
			}		
		}

My error:
Assets/GenerateWorld.cs(31,41): error CS1502: The best overloaded method match for `UnityEngine.Object.Instantiate(UnityEngine.Object, UnityEngine.Vector3, UnityEngine.Quaternion)’ has some invalid arguments

There should be the issue with the “Cube”, as Vector3 and Quaternion seem fine.
Can you post the code where variable “Cube” is declared? I guess it’s supposed to be a prefab. If so, have you set the prefab value in Inspector?

This line:

Instantiate(Cube,new Vector3((float)x,(float)y,(float)z),Quaternion.identity);

should be:

Instantiate(Cube,new Vector3((float)x,(float)y,(float)z),Quaternion.identity) as GameObject;

for the instantiate command in c# you need to cast it to a gameObjec like this

GameObject clone;
clone = Instantiate(Cube,new Vector3((float)x,(float)y,(float)z), Quaternion.identity) as GameObject;