Entertaining fans for decades, the Teenage Mutant Ninja Turtles are typically defined by their unique personalities and endearing family dynamic. The usual TMNT story is a blend of exciting ninja action with a childlike, yet amusing, sense of humor. Not all tales of the TMNT adhere to this lighthearted, family-focused story template, however. One upcoming story leaves only one turtle alive, taking a much darker and isolated approach to this specific hero in a half-shell.

Set 20 years in the future, TMNT: The Last Ronin will be a five-issue limited series which imagines one of the turtles in an Old Man Logan/The Dark Knight Returns-style dystopia.

Although the identity of the surviving turtle is unknown -- the series debuts Sept. 9 from IDW Publishing -- he carries the weapons of all four brothers, seeking to avenge his fallen family members. The Last Ronin was conceived in 1987 by TMNT co-creators Kevin Eastman and Peter Laird, during the publication of the original Mirage comic book series.

Finally returning to the idea over 30 years later, Eastman is scripting the Last Ronin alongside Tom Waltz, his longtime co-writer on the fan-favorite IDW TMNT series.

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Last Ronin Walking through water

With all of this information in mind, the question remains: Who is the last surviving turtle? Based on everything revealed about The Last Ronin so far, the most likely candidate is the youngest turtle, Michelangelo.

Considering the context in which Eastman and Laird conceived the Last Ronin, Michelangelo is also the most surprising choice. Michelangelo was the turtle who received the least attention in the original Mirage comic book series, since Leonardo was the leader and Raphael and Donatello were Eastman and Laird's respective favorites. Making Michelangelo the last surviving turtle, then, would be a welcome subversion of expectations, shining a much needed spotlight on the least-developed character of the original series.

The original comics, despite establishing Michelangelo's fun-loving personality, plant the seeds for the character's darker side as well. After fleeing to Northampton, following an ambush by the Shredder and his Foot Clan, the turtles fall into a state of disarray. Michelangelo, specifically, loses his fun-loving personality, isolating himself in a barn instead.

There, the youngest brother trains aggressively, even breaking through the barn walls. This pent up anger demonstrates Michelangelo's potential for a much darker character arc, perfect for The Last Ronin.

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It's the tragedy of this darker character progression which would make Michelangelo the most nuanced choice to outlive the other turtles. For so long, Michelangelo has been the heart of the TMNT. In the original Michelangelo "microseries" one-shot, Eastman and Laird flesh out the turtle's good-natured personality.

On Christmas eve, the turtle adopts a stray cat, naming him "Klunk," before stopping a band of toy thieves and delivering presents to children around the city (Michelangelo even dresses up as Santa by the end of the story). Shifting Michelangelo from this heartwarming tale to something as dour as The Last Ronin would be quite a shock. The surprise would make the story more interesting, showing just how far the heart of the TMNT has fallen without his family.

Despite all of the compelling reasons for Michelangelo to star in The Last Ronin, some fans still believe that one of the other turtles will be the last survivor of the TMNT. Leonardo is often depicted as the most well-trained and focused, while Raphael is the typical loner of the group. 

Yet, these qualities also make Leonardo and Raphael far too obvious choices. Perpetuating these character tropes would simply come off as repetitive. Choosing Donatello for The Last Ronin would be a nice surprise, especially since he's more of a scientist than a ninja. Still, Michelangelo would have more of an emotional impact, considering his previous goofy, kind-hearted characterization.

No matter who is the last surviving turtle, TMNT: The Last Ronin will certainly be a heartbreaking affair about a lone warrior who's lost his family. Even so, no turtle would be a better choice to emphasize these feelings of loss than Michelangelo.

TMNT: The Last Ronin #1 is slated for release on Sept. 9.

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