Number 1 (Big Guy and Rusty the Boy Robot Animated)
From Multiversal Omnipedia
Number 1 was the very first of the Legion ex Machina built by Dr. Roland Poindexter. Number 1 was the leader of the organization. He was destroyed when Poindexter shot him into a force field that One had imprisoned the Big Guy and Rusty within. He was the last of the original six to fall.