If the fourth live-action Teenage Mutant Ninja Turtles movie -- which would have potentially been subtitled either "The Next Mutation" or, apparently, "The Foot Walks Again" -- had gone ahead, the world could have met Evil April, Super Shredder and a fifth Turtle named after Jack Kirby. Now, we get to see what those characters might have looked like, as Kevin Eastman's concept art for the project has shown up at auction online, giving the world a chance to meet the Cyber Foot and other wild creations for the first time. Click through to see what we missed out on.