Sometimes heroes aren’t born, they’re built. Robots have been a long-standing staple of science fiction and superhero stories, and the Marvel Universe has no shortage of mechanical characters. Some are mindless drone soldiers, others act as servants, and then there are those that try to bring about the robot uprising and wipe out all organic life. And some synthetic beings become superheroes. These robotic heroes sometimes are designed to do good, while others are created for evil purposes and must rebel against their programming. Many of these heroes challenge not only what it means to be a hero, but also what it means to be alive.

While their bodies may be composed of metal, these robots have the hearts of true heroes.

Most people may know Baymax as the huggable healthcare companion robot from Disney’s Big Hero 6, but the comic version of the character couldn’t be more different. Baymax was built by the Japanese boy-genius Hiro Takachiho to be his guardian, He generally appears to be a large man. But when he needs to fight, Baymax transforms into one of two forms: Battle-Dragon and Action-Mecha, both of which give him increased strength and size. However, Baymax becomes more than just a bodyguard. Hiro replicated and uploaded his deceased father’s memories into the robot. As a result, Baymax became a dear friend and father figure to Hiro, and the pair joined the Japanese government-funded superhero team, Big Hero 6.