A Teenage Mutant Ninja Turtles co-creator has a previously unreleased story, described as dark. The co-creator, Kevin Eastman, is also teasing a follow-up to "The Last Ronin", with some outlets reporting a new installment titled "The Last Ronin 2" or "The Last Ronin – The Lost Years". Additionally, there are reports of other new TMNT projects, including a crossover with Batman and a new comic series.