He lays his life on the line in the defense of his adopted world. Every action he takes, and every modification he makes to his formidable body, is done to protect Earth. Megatron is usually depicted as having rose up form the lowly worker to become a champion in gladiatorial combat.
These amazingly detailed DIY models start as 4" square steel sheets & finish as amazing 3D models. Use the instructions to pop out the pieces, bend the tabs and connect them at attachment points.