Some of the biggest names in the industry are contributing to the newest Last Ronin comic.
IDW's hit Teenage Mutant Ninja Turtles: The Last Ronin saga continues to grow bigger. We already know that Kevin Eastman and his collaborators are hard at work on the third act of the Last Ronin trilogy, but there's also a new prequel spinoff in the works called TMNT: The Last Ronin - Training Day. Set in a 24-hour period during the original Last Ronin series, one shot Training Day will reveal how Michelangelo whipped young Casey Marie Jones into fighting shape before their showdown with Oroku Hiroto.
IGN has
debuted three new covers for
TMNT: The Last Ronin - Training Day #1. Check them out, along with the previously revealed covers, in the gallery below:
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| Art by the Escorza Bros. (Image Credit: IDW/Nickelodeon) |
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| Art by Kevin Eastman. (Image Credit: IDW/Nickelodeon) |
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| Art by Clayton Crain. (Image Credit: IDW/Nickelodeon) |
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| Art by Ben Bishop. (Image Credit: IDW/Nickelodeon) |
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| Art by Jonboy Meyers. (Image Credit: IDW/Nickelodeon) |
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| Art by Kevin Eastman. (Image Credit: IDW/Nickelodeon) |
Training Day reunites the original Last Ronin creative team, including writers Kevin Eastman and Tom Waltz, artists the Escorza brothers and Ben Bishop, and colorist Luis Antonio Delgado. Here's the official logline for the issue:
The training mission you didn’t see!
Michelangelo only has a short time to get young Casey Marie Jones prepared for battle against Oroku Hiroto. How can the Last Ronin distill a lifetime’s worth of training and knowledge into one day? Read the epic tale of action and legacy too big to fit into the pages of the original book, written and drawn by the original Last Ronin team!
This makes Training Day the fourth book in the Last Ronin saga, following the original 2020 miniseries, 2022's TMNT: The Last Ronin - The Lost Years, and 2023's TMNT: The Last Ronin II - Re-Evolution. As mentioned, Eastman and Waltz confirmed to IGN that another direct sequel is in the works, though we don't know the release date yet.
“This is going to be very personal for our heroes, whereas, it's business for the powers that be right now. And I also think, a character that I really look forward to exploring more is Jiro, because he has had a relationship with Casey. And maybe that was more genuine right now than it appears to be,” Waltz told IGN. “And so that's a dynamic I look forward to exploring. But I also think, when it comes to the family aspect, it's time for Casey Marie to step up and be that family leader. And we've thrown elements of the Hamato Clan into the mix too. So there's cool things happening behind the scenes that I think are going to make for some really, really exciting drama in the third volume.”
TMNT: The Last Ronin - Training Day #1 will be released on Wednesday, July 15, 2026. You can preorder a copy at your local comic shop.
Update (5/27): Michelangelo races to prepare Casey Marie Jones for war in just 24 hours as Tom Waltz reveals the emotional stakes, hidden history, and future-shaping consequences behind The Last Ronin’s newest chapter.
To celebrate,
AIPT has unveiled the first interview with Tom Waltz following the announcement of Teenage Mutant Ninja Turtles: The Last Ronin – Training Day #1! It’s clear this isn’t just another side story in the Ronin universe. Speaking with AIPT, Waltz digs into Michelangelo’s struggle to train Casey Marie Jones in just 24 hours, the emotional weight of stepping into the role of sensei, and how the story serves as a key turning point for Clan Hamato’s future.
Co-written by Kevin Eastman and Tom Waltz, with art by Ben Bishop, Esau Escorza, and Isaac Escorza, colors by Luis Antonio Delgado, Teenage Mutant Ninja Turtles: The Last Ronin – Training Day #1 hits comic shops July 15, with a Final Order Cutoff of June 8. The oversized 68-page issue explores the mission readers never saw as Michelangelo races against time to prepare Casey Marie Jones for the battles ahead.
Without further ado, get an inside look at the extra-sized one-shot below!
AIPT: Training Day takes place in a very tight window, essentially over 24 hours. What were the biggest storytelling challenges in capturing something as expansive as “a lifetime of training” within that compressed timeframe?
TOM WALTZ: To be honest, the fact that Michelangelo and Casey Marie have such little time to train together is one of the main drivers of the story. Mikey knows there’s no way he can provide his student “a lifetime of training” in the time they have together, so he has to lean into the idea that he’s training her as best as he can to “save lives” — including her own. He understands the risks that come with rushing things…but also realizes some training is better than none — and that Master Splinter’s journal could very well be the wildcard that expands/enhances Casey’s training should anything happen to him. The challenge for us as writers was finding a way to convey the idea that this limited training will have unlimited ramifications in Casey’s life, both as student and, ultimately, as sensei/teacher herself.
And who knows…maybe the old Ronin will learn a thing or two along the way too. As he so aptly stated in THE LAST RONIN #1: “Old dog. New tricks.”
AIPT: Michelangelo is in a very different place emotionally compared to the original Last Ronin. How did you approach writing him here as both a hardened survivor and someone trying to pass on hope to Casey Marie Jones?
TW: Actually, since this story falls chronologically between issues #3 and #4 of THE LAST RONIN (first volume), Michelangelo’s mindset isn’t too far detached from where he was in issues #1 through #3. TRAINING DAY works as a kind of catalyst for his emotional condition moving forward. What starts out as a kind of desperate effort to teach Casey the skills that will help her survive becomes the first true glimpses for Michelangelo that his own personal battle isn’t only about avenging transgressions from his past, but also laying a foundation for a better future for those he cares about: April, of course, and now Casey Marie. In essence, it’s Casey’s youthful hopefulness and exuberance that rubs off on Mikey. He hasn’t lost sight of his mission to take down Oroku Hiroto…but he’s beginning to see that his mission isn’t the last for Clan Hamato, with or without him.
One specific aspect worth mentioning is Michelangelo’s struggle with “imposter syndrome”. He knows training Casey is the right thing to do, but his past failures and tragedies (and the constant critiques from his dead brothers) make him constantly question himself, wondering if he’s capable (and/or worthy) to play sensei/teacher. It may just take a surprise intervention from a certain someone (no spoilers!) for him to overcome his paralyzing self-doubt and understand that for him (and for all of us, Dear Readers) failure is what teaches us how to succeed. One cannot exist without the other.
AIPT: This story fills in a gap between issues of the original series. When you went back into that timeline, were there any surprises or new angles you discovered about these characters that weren’t apparent during the original run?
TW: Honestly, I wouldn’t say there were new angles necessarily, but instead angles that were always there waiting to be explored given the opportunity. As we were plotting, Kevin [Eastman] and I would share backstory ideas that we knew might never see the light of day but were still essential to the story we were producing in our original run. It all had to feel real for us, whether we showed it or not. So, when the time came to sit down and write TRAINING DAY, it was like delving into real memories…real history…and it’s exciting (and cathartic) to be able to finally show it to our readers. We’re not reinventing the wheel here (if it ain’t broke, why fix it?) — we’re just exposing a few more spokes in the grand design, naturally incorporating (and expanding upon) concepts and scenarios from not only the original THE LAST RONIN, but from THE LAST RONIN: LOST YEARS as well.
AIPT: The idea that “the threat won’t wait for you” gives the book a sense of urgency. How did that philosophy shape the pacing and structure of the training itself?
TW: The ticking timebomb aspect to the situation facing both Michelangelo and the Resistance is pushing TRAINING DAY’s narrative. What we’re trying to do is funnel it down to a more personal scenario — teacher and student. Mikey’s thinking, “I gotta train this kid fast for her sake.” But what he begins to quickly realize is that in training her, he may be providing the essential knowledge and tools to ensure future success for the Resistance and Clan Hamato as a whole…or at least give them a fighting chance. Like a pebble tossed in water, creating a ripple effect (and that ripple effect is on full display in THE LAST RONIN: LOST YEARS, THE LAST RONIN II: RE-EVOLUTION and soon, THE LAST RONIN III).
AIPT: Casey Marie Jones is stepping into a legacy that carries a lot of weight. What defines her as a student, and how does she challenge Michelangelo as a teacher?
TW: Oh, Casey Marie is a terrible student from the get go! As much as she’s April’s daughter, she’s got a lot of her dad (Casey Jones) in her too, and we really dig into that in TRAINING DAY…especially her stubborn side. She wants to learn, yes…but she’s not quite ready to sit back and be told what to do without pushback and attitude. In all fairness, she’s been fighting her whole life, so she’s having a difficult time going back to the basics, so to speak. She wants Mikey to show her the “good stuff” right off the bat, and quickly loses patience when her sensei insists you can’t have the good stuff without the “boring stuff” first. The challenge for both student and teacher is to find a mutually beneficial middle-ground in the short time they are allotted to make the training count. (For our LOST YEARS fans, we see reflections of Mikey’s time training with Master Yip in TRAINING DAY.)
AIPT: You’ve described (To
EW) this as both a “love letter” and a conversation with fans. How much did fan response to the Ronin universe influence what you chose to explore in this story?
TW: Well, we absolutely love hearing what fans, retailers, and critics have to say about our work on THE LAST RONIN series, from the first volume through everything that has followed. Fortunately, most of what we hear and read has been tremendously positive (although we truly appreciate honest criticism as well), and we wanted to continue to give our amazing readers more of what has made them fall in love with consuming this epic drama as much as we have creating it. TRAINING DAY is a story Kevin and I have always wanted to tell since we started this journey, and fans have echoed that desire over the years, so this is our chance to further our collaboration with the many RONIN fans out there…to continue our so-called conversation by letting the characters do the talking (and showing) for us. At this point, it feels like THE LAST RONIN has taken on a life of its own, and we’re all (creators and fans alike) just along for the ride together. It’s a wonderful synergy I’ll forever cherish.
AIPT: With multiple artists contributing, how did you ensure the visual storytelling stayed cohesive while still capturing different aspects of the training and tone?
TW: From the very start, we’ve been blessed with tremendous artists on THE LAST RONIN series. The Escorza Brothers, Ben Bishop, SL Gallant, Andy Kuhn, Freddie Williams II and, of course, Kevin Eastman, have all come together to position THE LAST RONIN as one of the most visually striking comic books/graphic novels in the world. As writers, Kevin and I do our best to play to their strengths, making sure that their individual talents and strengths stand out without complicating the visual story being told by keeping things consistent — one art team on the present story, one art team on flashbacks, one art team on first-person narration, etc. But throughout it all, our ace in the hole has been colorist extraordinaire Luis Antonio Delgado, whose brilliant palette continues to seamlessly unite the various art styles into one beautifully cohesive package.
AIPT: Looking at where Training Day fits within the larger Roninverse, what does this story reveal that will change how readers interpret Casey’s role and evolution moving forward?
TW: Without giving too much away, THE LAST RONIN III will find Casey Marie in a similar situation that Michelangelo was at the beginning of THE LAST RONIN — her beloved city under siege and she and her family dealing with multiple devastating losses that require a response. Will she move forward along a path laid in TRAINING DAY — one comprised of discipline, honor, and hope — or will she fall into a dark trajectory of vengeance and hate like the Ronin did after his family (and many friends) were killed? Stick around, Sports Fans! All will be revealed in THE LAST RONIN III…and everything that has come before it (including TRAINING DAY) will have a massive impact.
AIPT: You’re doing more superhero work at Marvel Comics with some solo writing, but also co-writing with Al Ewing on Knull. AND you’re back to working with Kevin Eastman on Training Day. Can you talk a little bit about your writing process, particularly with different writers versus solo?
TW: I’ve been truly enjoying the work I’ve had the opportunity to do at Marvel. I’m a diehard superhero fan, so any chance I get to play with classic caped and cowled characters is always a blast, and Marvel has been amazingly welcoming and open to let me scratch that creative itch on various titles and characters. Funny thing is, my TMNT experience has been instrumental in making the transition a smooth one. I mean, I got to write Wolverine a few times (Raphael with claws) and Knull (Rat King, anyone?), so I feel like I’m in familiar territory in some ways, and not starting from zero, so to speak, allows me to then expand on the Marvel-centric aspect of those characters that has made them so popular and endearing in the first place. And Marvel’s not done with me yet, folks…but that’s all I can say for now but look for some exciting announcements in the near future. (Now, I just gotta find a way to get those DC folks to let me join their fun too LOL.)
Working with Al Ewing on KNULL was a fantastic experience. Al’s a comic-book wunderkind (and a walking Marvel encyclopedia), so I was more than happy to follow his lead when the mighty Marvel editing team of Jordan White and Emerald Bensadoun invited me onboard the limited series…and was absolutely humbled at how open Al was to my own thoughts and ideas from the very start. In the end, it felt just as much mine as his, and I have his selfless willingness to share the spotlight to thank for that.
And, of course, working with Living Legend Kevin Eastman (my brother from another mother) is always the treat of treats for me. We get together, throw all kinds of crazy ideas against the wall, see what sticks…discuss, debate, decipher…then, once we have our story, we put it on wax (as the Beastie Boys once rapped). We’re like two mad scientists in a lab, simultaneously shouting “It’s alive! It’s alive” in twisted harmony. There’s nothing like it, and I wouldn’t change it for the world.
And I maintain an exceptional relationship with IDW Publishing as a whole. Truly my family in so many ways.
As for my solo writing adventures, that’s usually done in my messy office, on my old (very old) computer, a coffee mug filled with the blackest coffee possible nearby, with my trusty husky Everest at my feet, working always to overcome that same imposter’s syndrome Michelangelo (and so many of us in this world) struggle with. Thankfully, the characters that channel through me always guide my way…so I let them use me to tell their stories, never failing to be surprised at what they have to say, show, and share.
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Originally published: April 23, 2026.
