Lego Cake

Here is a cake I made for a friend's son who is an avid Lego enthusiast. I guess it looks simple enough, but I think this was probably the most challenging cake I've made to date...because there is so little there to cover your mistakes :)
I think I used a total of 7 cake mixes to make this, as well as some Little Debbie snack cake things (cherry sandwich something or others) to make the studs? whatever those raised up parts of the Lego are called. This was extremely tricky, because if you get the proportions of the cakes or the studs wrong, it looks ridiculous. The cool thing about this cake was that each of the cake's inside matched the outside, like a real Lego brick would be, since I colored the batter to match the frosting. The whole thing is covered in buttercream, rather than fondant, for taste reasons, so that has a tendency to look sloppy, too...overall, I was happy that it came out at all, and that Jacob and his family liked it!