Lets say I have Gameobject 1, Gameobject 2 (length of 2), and Gameobject 3.
I want to make it so 3 = 1 + 2, having all the objects that are in 1 and 2.
GameObject one = new GameObject();
GameObject two = new GameObject[2];
GameObject three = new GameObject[3];
two.CopyTo(three, 0);
three[two.Length] = one;