Artist Mitch Gerads tweeted out the news, of a Riddler graphic novella, Batman: One Bad Day, drawn by him, written by Tom King. He tweeted "#BatmanOneBadDay THE RIDDLER, a 64 page OGN by @TomKingTK and myself! My genuine long-time dream book, and @TomKingTK delivered the absolute perfect script for it. I've never been this excited to get a book into your mitts! I've been putting everything I have into every page." Adding "The Riddler is TERRIFYING." One Bad Day refers to Batman: The Killing Joke by Alan Moore and Brian Bolland, also a 64-page story, and the intimation is that this is meant to be a Killing Joke but for The Riddler.
The Riddler was first Edward Nigma, later Edward Nygma as well as Edward Nashton. One of Batman's main rogue gallery, he was created by Bill Finger and Dick Sprang for Detective Comics #140 in October 1948. A criminal mastermind obsessed with setting u crimes that can be solved through the examination of complex riddles, he became popular after his portrayal in the Batman 1966 TV series played first by Frank Gorshin and then John Astin, with Jim Carrey playing him in the 1995 Joel Schumacher movie Batman Forever, Cory Michael Smith in the 2014 TV series Gotham, and most recently a starring role by Paul Dano in this year's The Batman.
Batman: The Killing Joke was a 1988 DC Comics one-shot graphic novel that gave an origin to the Joker, but also saw him attempt to drive Commissioner Gordon mad with grief, the idea that the Joker became the Joker because of one very bad day – and the same with true of Batman as well. It is considered the definitive Joker story, In guess DC would really like the same for The Riddler, and do it in the comics rather than wait for the TV show spinoffs.