Biographical information

Homeless (formerly)
Prison (formerly)
Foot Headquarters (formerly)
Splinter Dōjō, Mutant Town, New York City, Earth




Jennifer (by Ivan)

Weapon(s) of choice



Foot Assassin (formerly)
Foot Clan chūnin (formerly)
Splinter Clan instructor (currently)


Silas (formerly)
Foot Clan (formerly)
Splinter Clan (currently)

Physical description

Blonde (as human)
Bald (as turtle)

Bandana color


Out of universe information


First appearance

Order from Chaos, part 1 (as a human)
City at War, part 3 (As a Mutant)

Created by
Teachers and Students

Some TMNT stuff really isn't for little kids.

Jennika, also known as Jenny or Jenn for short, was the ninja chūnin of Splinter's Foot Clan, a dear friend to the Turtles and for a time was a love interest to Casey Jones. Originally human, she is now a mutant turtle after her life was saved by an emergency transfusion of mutagenic blood donated by Leonardo due to her loss of blood. After the City at War arc she moved to Mutant Town a part of New York inhabited by people who were mutated because of Old Hob and his bombing at Union Square Park. There she along with the other turtles and her fellow ex-foot soldier Alopex founded the Splinter Clan and built their own dōjō. She eventually started a band called Created in Darkness and began dating her friend Sheena.


Jennika was a young Foot Assassin, and a loyalist to the Foot Clan rather than to The Shredder. As a young girl, she was driven from her home when she found her father beating her mother, and lived on the streets afterwards. She took up with Silas, a young man who pulled her into a life of petty robbery, which ultimately led to her imprisonment as an accessory to murder.

Her first encounter with the Foot took place in prison, where an imprisoned Foot ninja defended her from other convicts and became her fast friend. The woman trained Jennika in secret as they plotted to escape the prison, but Jennika's friend was killed by another inmate just as they had gained their freedom. She found her way to the Foot and became one of their number, using her newfound skills at killing on the woman who had murdered her friend.

After Shredder's death, she distrusted the new leader following his death and questioned why this "rat" was fit to lead. She was convinced that he was weakening the Foot Clan with his unwillingness to kill without hesitation, and saw his merciful actions as signs of cowardice and weakness, believing that quick and deadly action was necessary to remain supreme.

As a result, she secretly associated herself with Darius Dun and the Street Phantoms. When the Phantoms attacked the Foot Clan, Jennika attempted to kill Splinter in single combat, but was defeated quickly.

After Splinter humbled her, she began to realize the error of her ways, and pledged her service to the Foot's new leader and his sons. Splinter believed in her change of heart, though he still had to penalize her for her act of disloyalty. After being impressed by her faithful service, he assigned her to guard the tomb of the Shredder, which she did faithfully until she was attacked by Kitsune and Alopex.

During the Triceraton invasion, it was confirmed that Splinter had selected her as his new chunin. However, she was still very impulsive and required his guidance. She was also deeply conflicted about Splinter's plans to kill Commander Zom, eventually arranging for the Turtles' escape from the Foot Clan headquarters in order to stop him. She was not penalized for her disobedience after the invasion ended, and was instead sent out by Splinter to protect Casey Jones. The two eventually began to enjoy each other's company and develop feelings for one another as time went on.

After the Turtles brought a number of orphaned children to the Foot Clan, Jennika helped care for them. When Karai returned from Japan, Splinter was willing to cede leadership of the Foot to her were it not for her insistence that the children be trained as soldiers. Jennika came to Splinter's aid as negotiations failed and Karai was denied the Gauntlet. With her attempt to reclaim leadership of the Foot having failed, Karai declared that war would be coming to Splinter and those loyal to him.

A short while later Karai reached out to Jennika for a truce. Karai attempted to sway the chunin's loyalties away from Splinter, but Jennika refused. Having fully expected this possibility, Karai stabbed her as the first act in her war to retake the Foot from Splinter.

In a desperate attempt to save her life, the Clan Hamato and their allies took her to Harold Lilja's laboratory. There, Harold, Libby, and Lindsey attempted to use the Ooze to heal her, as it had done for John O'Neil. However, the vial of ooze was shattered during a firefight when the Earth Protection Force and Metalhead attacked. Seeing no other option and with time running out, Donatello had Leonardo transfer his blood to her to aid her recovery. This had the desired effect, but also mutated her into a turtle.

Waking up as her mutation completed, Jennika was initially confused about the changes she had undergone. Donatello confirmed what had happened and explained what was going on as they made their way to Brooklyn Bridge's home for shelter, escorted by the Purple Dragons. After repelling an attack from Karai's assassins there, Jennika reconciled with Casey, who put aside his initial lukewarm reaction to her change once he saw her saving her friends.

Following Splinter's sacrifice to put an end to the Dragon, Jennika lived in the New York ghetto now known as Mutant Town, where she is introduced to Mona Lisa when saving her from Bandit and Puggle. After all of the turtles regrouped and started a dōjō as the Splinter Clan, Jenny was inducted as one of the clan's sensei. As well as this function, she essentially acts as a "big sister" to the other Turtles.

Jennika and Casey drifted apart, although the two have met up on occasion and while awkward, do not seem to be on poor terms. Jenny later started dating Sheena Murphy the mutant pig lead singer of After the Bomb. Although reluctant to do so, she was convinced to start her own band, Created in Darkness, when a time-travelling Lita arrived to tell her that without this band, the Turtles would lose sight of themselves and suffer heavy losses in a war with the Foot Clan.


Jennika has a tough girl persona but is really sweet and caring. Like Raphael, she has a lot of anger issues but is better at controlling her temper than he is and has better manners. She is also a big fan of heavy metal music.



  • Antoni Rosetti, Jr.:
  • Cellmate:
  • Children of Saint Robert's Orphanage:
  • Diamond:
  • Alopex:
  • Leonardo:
  • Mona Lisa: They became quick friends after Jenny saved Mona from Mighty Mutanimals enforcers Puggle and Bandit.
  • Raphael:
  • Sally Pride:
  • Sheena:She befriended her over their shared interest in music. Sheena also became her student at the dojo. Eventually they formed a romantic relationship.
  • Lindsey Baker: Jenny and Lindsey knew of each other, but were never known to associate until the City at War arc after Jenny had been impaled on Karai's Kira no Ken. Since Lindsey was the Mutanimals' scientist and had access to a limited supply of Hob's ooze stash, the turtles asked for her help, and she stole what little ooze she could and brought it to Harold's lab so that it could hooked up to Jenny's intravenous tube and heal her wounds. When Metalhead raided the lab and the ooze was destroyed by a stray bullet, Lindsey accompanied Jenny, Leo, Donnie and Mikey as they fled. Lindsey was still with them when Jenny was transfused with Leo's mutagen-infused blood in a last ditch attempt to save Jenny's life.
  • Lita:
  • Michelangelo:
  • Mother: Jenny's mother was abused by Jenny's father.
  • April O'Neil:
  • Donatello:
  • Mrs. Gonzalez:
  • Casey Jones: Casey and Jenny seem to have a close and peaceful relationship. Casey came to visit her at the orphanage to bring ice cream and invited her to a date after work, where they talked about each other's home lives. He was in shock over Jenny's mutation but soon came to realize she is still the same afterward.
  • Hamato Yoshi / Splinter:
  • Weasels:


  • Madam Null:
  • Father: Jenny's father was an alcoholic who was abusive to her and her mother. One day when Jenny was still young, she walked into their apartment to find her father beating her mother. When Jenny's father turned his rage on Jenny herself, she ran away and didn't return.
  • Darius Dun: Jennika knows Darius Dun as the leader of Street Phantoms and was determined to end his organization. Splinter ordered Jennika to kill Dun, to which she unquestionably obeys and murders him by fatally jabbing him through his chest in front of remorseless Splinter and horrified Turtles.
  • Kitsune:
  • Zodi:
  • Lucia Rosetti:




Jennika was a young woman with very short blonde hair and blue eyes.

As a Foot Assassin, Jenny dressed exactly like the other Foot Assassins, and her mask made her appear like any other. But after she was demoted and disciplined for her temporary defection to Darius Dun, she wore a variation of the typical Foot Ninja garb, including a top and trousers, but seldom ever appeared wearing a mask. Jenny continued to wear similar unmasked outfits even after the other turtles left the Foot and she became Splinter's new chūnin.

Jennika carried and fought primarily with a pair of metal claws, but could also sometimes be seen wielding a katana.


Jennika has retained her blue eyes but very little else remains of former human appearance. Anatomically, she has three fingers on each hand and two toes on each foot just like the other turtles, and her skin is pale green. This makes her appear physically much like the other turtles, with few or no visible secondary sex characteristics that would reveal her gender by appearance alone.

Jenny usually wears an outfit similar to what she wore as Splinter's human chūnin in the Foot Clan, including a top and trousers suitable for ninjutsu, but now with the addition of a yellow bandanna in the same style as the other turtles and echoing the color of the blonde hair she used to have. With the exception of certain concept art and cover art, she has never been depicted wearing the traditional "naked" turtle gear of only belts, harnesses and bandanna, nor has she even bared her plastron topless. Nevertheless, she does not appear out of place even with the clothes she wears, as the other turtles also started wearing fully-clothed outfits more regularly since TMNT #101.

Jenny's selection of weapons as a mutant is much the same as before she mutated.

Powers and abilities

  • Ninjutsu: Jennika is well-versed in the art of ninjutsu, including not only hand-to-hand and armed combat, but stealth, espionage, escape, and more. Unlike the other Turtles, she was trained specifically for the purpose of assassination, and has taken lives quite brutally on more than one occasion.
  • Athleticism: Although she likely is not as well-versed in this as the other turtles, she is incredibly nimble and boasts athletic strengths far beyond even most trained athletes.
  • Childcare: Jennika was tasked with the supervising and care of the children of Saint Robert's Orphanage more than any other member of the Foot Clan or Clan Hamato, that was seen.
    • Pedagogy: Jennika taught basic martial arts techniques to these orphans.
  • Mutant turtle physiology: As a mutant turtle, Jennika has the advantages (and potential disadvantages) with being a bipedal turtle of humanoid size and stature. Most prominent, is her shell, a natural armor comprised of the carapace and plastron. It is unknown what other specific enhancements she has at this time.

Weapons and equipment

  • Foot Assassin uniform: As a Foot Assassin, Jennika wore a specific uniform, including striped sleeves and a menacing red mask.
  • Claws: As a Foot Assassin, her clawed weapon was a glove with bladed fingers, sort of a combination of the tekkō-kagi with "neko-te", and reminiscent of Freddy Krueger's trademark weapon, but with claws more in length of a tantō. Post-mutation, she wields traditional tekkō-kagi the likes of which were utilized by Oroku Saki, only with four blades.
  • Katana: Outside of her Foot Assassin garb, Jennika normally carried and wielded a single katana.
  • Bandana: Post-mutation, Jennika takes up wearing a yellow eye-mask bandana, similar to the other turtles.
  • Joint wraps


  • Not counting cameos from other continuities or forms who appeared only in dreams, Jennika is the sixth mutant turtle character introduced in the IDW continuity, after the four Clan Hamato brothers themselves and the late Slash. She is also the first IDW mutant turtle who is female.
  • Jennika is one of the few mutant turtles in any TMNT continuity who is female. Past examples have included April O'Neil in the Archie continuity (only temporarily mutated), and Mei Pieh Chi a.k.a. Venus de Milo in Ninja Turtles: The Next Mutation.
  • Jennika's mutant form was designed by Sophie Campbell. Jennika's bandana is yellow, similar to Campbell's fan character Artemisia, but the color was requested by Tom Waltz to match her hair color, and he was unaware of Artemisia—the color synchronicity was purely incidental.
  • The idea of Jennika becoming a mutant turtle was tossed around for three years before being finalized.[1]
  • In issue #101, Jennika comments that Raphael is like her "horrible kid brother." The topic of Jenny's age relative to the other four Turtles is a complicated one, as on one hand their physical turtle bodies are only a few years old, but they are reincarnated humans who were born centuries before in feudal Japan. But since the Hamato Sons died as teenagers and reincarnated socially still teenagers, this may imply that Jenny's age is chronologically older than the social age of at least Raph and his socially younger brothers Donatello and Michelangelo. (Leonardo is socially older than Raph, which would make his social age unclear in relation to Jenny.) In "The Cure for You", Jennika mentions that Silas abandoned her 10 years prior to the story's timeframe, and she was a teenager when last they were together.

See also