So What's Really Under all that AT-AT Armor in Star Wars?

A cool new t-shirt design has unveiled the secrets that lie under all that AT-AT armor from Empire Strikes Back. The design is an X-Ray of one of these mechanical beasts that show us the skeleton of the beast that resides within. 

This whole time we thought they were giant robots, when in "reality" they are giant monsters. The design comes from teefury.