Michelangelo is a box turtle who was mutated to become part human. As a box turtle, he is able to close the openings of his shell to make it even more difficult to be hit by an attack. He is an artist and skateboarder, and initially uses nunchucks, but after they are destroyed he wields a kusari-fundo instead, which possesses a "mystical whip" ability. He is the youngest of the Turtles.
Michelangelo has teal green skin, yellow-orange circles painted on his shoulders and thighs, a bright yellow plastron with neon pink and blue lighting bolt stickers on it, and a navy teal carapace with yellow-orange designs. He has black eyes, a small gap on the right side of his upper jaw, three fingers on each hand and two toes on each foot.
Mikey wears an orange mask over his eyes (with short mask tails), orange wristbands and color-matching socks and orange knee pads with faces drawn on them (dead face on the right and smiley face on the left). He also wears a light brown belt around his chest and strap over his right shoulder, as well as a Turtle emblem over his heart.
Michelangelo is very similar to his previous incarnations as he loves to crack jokes and is generally more optimistic than his brothers. He has a passion for art, presumably of many kinds as he is shown to have a passion for painting and cooking. Mikey can be very oblivious to dangerous situations, mostly unaware of what kind of trouble he could be in. He also tends to be naïve, but also kind-hearted.
Mikey is also shown to be attuned to pop culture, based on some of his word choices, his knowledge of celebrities (like Rupert Swaggart) and his love for rap music. However, Mikey has mixed appreciation for certain retro/old school icons, such as his disappointment with the dated graphics from the Lou Jitsu video game.
Mikey is also easily frightened when in a scary situation, and often has the tendency to react quickly by screaming rather loudly and not stopping screaming for a while. To add to his oblivion, he does not think things through when he's scared.
Mikey also gets upset or angry if things don't go the way he hopes, such as when he snaps whenever someone tries to sabotage his love for pizza, which can allegedly make him unstable. He also does not appreciate being looked as being dependent, as such in "Hot Soup: The Game", where Mikey is eager to do things on his own, much to Raph's disapproval.
When he uses the "Dr. Delicate Touch" method, he sometimes starts off as being sweet but quickly becomes angry and straight to the point. Examples of such would be seen in episodes like "Pizza Pit" or "Bullhop". Mikey is shown to be very competitive as seen in "You Got Served" when he is determined to win despite Leo saying it isn't a competition.
Like his brothers, Michelangelo began his life as a baby turtle in Baron Draxum's laboratory. Wishing to make mutant soldiers, the Baron used Lou Jitsu's DNA to mutate Michelangelo into an anthropomorphic turtle. He was taken from the lab by Lou Jitsu, along with his brothers.
Youngest of the group, Michelangelo has a wild and colorful personality. He's an artist and spends his time tagging the Turtles' lair—and his own box turtle shell—with graffiti. He's an eternal optimist and an absolute natural at ninjutsu.
- Mystic Whip: Perhaps the oddest of the weapons found in Draxum's lair, Michelangelo possess a kusari-fundo with a sphere weight with spiked ridges. The sphere becomes a flaming head when Mikey wills it, and he can move however he wills it. It is also capable of lifting enormous objects.
- Strength (Due To Mutation)
- Speed (Due To Mutation)
- Raphael: Mikey doesn't like it when Raph becomes overprotective of him. But he does love him deeply.
- Donatello: Mikey is exceptionally close to Donnie, often seen clinging to his side. The two go on a minor adventure together in "Repo Mantis". Mikey is often seen with Donnie such as in "The Ancient Art of Ninja Hide and Seek" when Leo and Raph work on their own but Mikey chooses to stick with Donnie
- Leonardo: Mikey is competitive towards Leo but does love him deeply.
- Baron Draxum:
- Meat Sweats:
- Warren Stone:
- Foot Clan:
- Foot Recruit: Mikey is the first turtle to meet Foot Recruit in "Hot Soup: The Game". They fight over the game and Foot Recruit tries to destroy Mikey but they are able to relate to each other in terms of wanting to complete their solo mission. He refers to her as a "Frenemie". (How to Make Enemies and Bend People to Your Will)
- Repo Mantis:
- Foot Recruit:
- Big Mama:
- "You must be THIS rad to ride that ride." - After doing a cannonball with his brothers into a pool
- "Yay, arts and crafts!" - Upon seeing the Origami made by the Foot Lieutenant
- "April's memes are SO lit!" - After seeing the Turtle-Potamus meme April sent.
- Mikey says "Cowabunga" as his catchphrase on the series, rather than "Booyakasha", which was the catchphrase of his previous Nickelodeon incarnation.
- He also often says "Omigosh!".
- According to the writers, he's the sweet and loving turtle of the team.
- He is revealed to have a close relationship with Leo, who takes him under his wing.
- Mikey is a passionate artist in this series.
- He is shown to put stickers on his shell.
- He also loves to decorate the Lair with graffiti.
- Brandon Mychal Smith stated in an interview that Mikey likes extreme sports.
- In the original Mirage Comics' The Passing, Mikey's training weapon was also a kusari-fundo.
- This version of Mikey is the second ninja turtle to have a gap in his teeth.
- Despite being referred to as a kusari-fundo in the official character releases, Mikey's new weapon more closely resembles a chigiriki.
- As shown in "You Got Served", Mikey sees everything as a competition.