Carter Brown is the main antagonist of the episode "The Future is Cardboard" in the 2018 animated series Craig of the Creek.
Carter used to play with Zoe & the others, but there city was never enough for him. Carter always wanted it to be taller, have drawbridges, & a Faucet (which he wanted to do for some reason). Zoe & the others told him they didn't want to play that way & Carter stormed off In anger, never to be seen again.
In "The Future is Cardboard," Carter introduces himself to Craig and his friends after he had watched Craig make a box he had left out into a recliner. Carter then takes the three friends to a city he had created made out of cardboard. Surprised that it was empty, Carter explains that he was originally apart of another group of kids who constructed items out of cardboard, but he left because he felt that they didn't realize his brilliance. When Carter suggests that Craig help him move the New Cardboard City to an old cardboard city, this causes a rift to form among Craig, Kelsey, and J. P. and they leave. Carter insists to Craig that they would soon see the hard work that was put into the plan, and this inspires Craig to continue to assist him.
While looking for their tree stump, Kelsey and J. P. discover the original cardboard city, where they learn the truth about Carter. Suddenly, a gigantic robot made out of cardboard invades the city, with Carter making it his goal of crushing his former friends for not acknowledging him as the genius he assumed himself to be. Craig tries to fight him only to be thrown into a trap. Realizing that his hands could also be used for construction, Craig tears his way through the robot causing it to detonate. Carter escapes the robot as it was exploding, and gets cornered by Zoe. Carter explains to her that he did all of this for her, but Zoe forces him to retreat. He ends the episode by vowing that he would have his revenge.