Leading up to a character is fully realized on-screen, several ideas are presented before a final design is chosen. For someone (something?) like Ultron, that meant several different possibilities before the filmmakers finally chose what millions of moviegoers saw in Age of Ultron. He could have looked much different—that concept with a blue hue is amazing! He just wouldn’t have been as menacing.

Following the film’s May release, concept artist Andy Park, who has been with Marvel Studios since 2011’s Thor, shared a handful of designs considered for Ultron, and I wish all of them would have made it into the final movie. It’s cool to see the little nuances that are changed and tweaked before a final design is agreed upon. I thought Ultron looked great in Age of Ultron—menacing, powerful, and, above all, incredibly believable.

Check out the images above and let us know which concept you like the most. They all have varying degrees of realness. A few look like they were directly inspired by armor from the Middle Ages, while others are more humanlike in their appearance. For reference, we’ve included a few shots of the final Ultron design from the movie.