Tetrahedrons Cloud!

Hi guys! I'm going crazy with these tetrahedrons! Grashopper is awesome! :) but i have some problems:

1. I can do a tetrahedron, also a number of tetrahedra in the xy plane, but when I try to repeat on the z axis I can not, here's the problem, because the movement is not only on the z axis, I can't do a serie with this vector. I tried to do it by differents columns or rows but its impossible for me.

2. Another problem. How I can fill a surface like this with tetrahedrons? What about change the size of this tetrahedrons? Is it possible like a fractal? :Si'm still working...

Thank you!

Finally I have completed the cloud!! I am a little bit fool. With the help of some sketches it was not so difficult! :).

I found the movement pattern of my tetrahedrons

Then I found the points inside my surface!

But now I cant create lines between points like in the begining of the process, with the pattern with points 1, 2, 3, 4. What I have to do?

?????????? 

Bye!!!