Where do I get the upgrade to destroy gray clean cubes?

[k4ever]

Im on level 16 and I cant finish it. I tried many different ways and it was impossible. Finally I gave in and searched for a youtube video to see how the level had to be done. To my surprise it seems you need an upgrade to destroy the gray clean cubes without cracks. I remember in one of the previous levels they told me an upgrade was coming, but I still havent gotten anything. I tried searching for an upgrade machine in any previous level I finished in order to to see if I missed one, and there isnt any. What are the levels in which you get each upgrade?

[k4ever]

Nevermind, I just saw another one and it can be finished without it. From now on ... no help whatsoever!

Shame on me :(

[Shad0WeN]

yes, shame on you for giving up so easily. I didn't really get stuck until level 34 (Child's Play), but then thought about it for a bit and the solution came to me

it's levels 19 & 33 for the drill upgrades btw