Master Splinter is a mutant rat who serves as the wise master and adoptive father of the Teenage Mutant Ninja Turtles. He’s always there to give handy advice to his sons and their friends, protect them when needed, and ensure that those he cares about are able to live the best lives they can. He can also dish out a beat down to the toughest of foes.

With there being so many different versions of Teenage Mutant Ninja Turtles out there, it also means there are that many versions of Master Splinter as well. He may serve the same purpose for each take, but he often has different characteristics. Sometimes he’s a more serious foil to the Turtles while others he proves to be more of a comic relief old guy. Regardless of how he’s handled, he’s still ultimately the same old Splinter, except when it comes to one major detail.

Each version of the wise old rat can be separated into two categories regarding his backstory. Some takes on the character have Splinter being a rat who was mutated just like his turtle sons. Others have him being a human named Hamato Yoshi who was mutated into the rat we know as Splinter. There are mutants in the TMNT lore that were animals who were mutated after being exposed to the ooze, as well as mutants who started as humans who were transformed into their animalistic forms, so either backstory for Splinter technically does fit into the rules of this world.

Both of these versions have been featured in their fair share of stories, and fans have often debated which one works best for the character. Fans who prefer Splinter starting as a rat who learns martial arts before ever mutating have a lot supporting their argument. The very first version of the character in the original Mirage comic book was a rat who became mutated. This also puts him through the same changes as his adopted sons. Him living his life as an animal and learning to walk, talk, and act more like a human after mutating aligns his experiences with the Turtles.

Also, being a New York City street rat allowed him to see the downsides of humanity, making him concerned about how to approach them, leading to some interesting stories covering themes of humanity and treating others who are different, like in Teenage Mutant Ninja Turtles: Mutant Mayhem. Oftentimes, this version is originally Hamato Yoshi’s pet rat and learned martial arts by watching him practice. This puts Hamato Yoshi on a pedestal as a more mythic character while keeping the rivalry between Splinter and the Shredder personal after Shredder causes Yoshi’s demise.

With all that being said, I’m personally in the camp that prefers Splinter actually being Hamato Yoshi who was mutated into a rat. It makes the rivalry between Splinter and Shredder significantly more personal. It turns their backstory to one of friendship, betrayal, sadness, and revenge. Much more emotion can come out of such a story.

In many of the stories featuring Splinter as Hamato Yoshi, since he was trained alongside Oroku Saki (The Shredder) and they ran their dojo together, there are arcs that touch on the legacy of the Foot Clan and how it compares to how the Turtles are trained. The contrast between how Splinter trains his sons compared to how the Shredder trains his army is focused on more.

The stories in which Splinter and Hamato Yoshi are the same have also gone even deeper depending on the version. For instance, the 2012 Teenage Mutant Ninja Turtles series added the extra twist that Karai was actually Splinter’s daughter who he thought died when she was a baby, but Shredder raised her to do his bidding as revenge for marrying the woman they were both in love with. If Splinter was nothing more than a rat, stories that intense just couldn’t happen.

Plus, how would an ordinary rat learn martial arts at all? Obviously, this is a franchise about mutant animals, robots, ninjas, and aliens, so a suspension of disbelief needs to be assumed. However, if he’s going to be one of the greatest martial arts master the world has ever seen, reading a book, watching Internet videos, or watching someone else training isn’t going to cut it, especially for a house pet or wild animal. Having him be a human who learned martial arts over the course of his life to become a master makes more sense.

Him becoming a rat mutant who’s forced to live in the sewers after living life as a human is much sadder, and him raising his sons to make the world a better place shows how much hope he still has. It’s overall more powerful.

If you’re someone who prefers Master Splinter being an ordinary rat who was mutated, I can certainly see why. Both versions lead to great stories and offer their own entertainment value. I just personally prefer the stories in which he was Hamato Yoshi before becoming mutated. I find them more emotional and interesting.

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