Title says it all. You've got 50 pieces to build one mech with at least two articulated limbs (legs, arms, tendrils, etc) in LDD. Might be a bit similar to another challenge that just recently got put up but building mechs instead of ships might add an additional layer of depth to it. Alternate form of the mech are fine, as long as it has one form where it's clearly recognizable as a legit mech.
So here's my first entry:
Der Cyberbulle:A robotic law enforcement unit created to ensure safety in the vast cyberspace of Cyber-Deutschland. Armed with a cyber gun and cyber handcuffs, he is well equipped to take on any kind of cyber scum out there.