- "I hope you won't forget me when you go to Junior High! ... You'll always be my students!!"
- —Ms. Mari, Mega Man Battle Network 6
Ms. Mari, known by her full name Mariko Ozono (大園まり子先生 Ōzono Mariko-sensei) in Japan, is a character from the Mega Man Battle Network series. She is a new teacher at ACDC Elementary School where Lan Hikari and his friends go, and their class is her first graduating class. She operates a NormalNavi that she uses to teach with and also participates in NetBattle tournaments in. She has a twin sister named Ms. Yuri who is identical to her and some mistake one for the other.
Given her appearance and status as a new teacher, Ms. Mari is most likely in her mid-20s. She has a strong passion for teaching and taking care of her students, and does not take any harm coming to them or seeing them leave lightly. She teaches a variety of different subjects including Virus Busting, and often has a small animal exhibit in her room. She will often work on weekends and after-hours and meals her class for any information she forgot mention in class, and keeps a close eye on slackers like Lan and Dex Oyama. Ms. Mari's role is greatly reduced from Mega Man Battle Network 4 onwards, but she gets to see her first class graduate together when Lan returns at the end of Mega Man Battle Network 6.
Though Ms.Mari doesn't appear in person during the events of Mega Man Battle Network 5, she was mentioned by Higsby (by her full name name Ms. Mariko) to have asked NumberMan to accompany her Navi as a bodyguard during the End Area event of Team Colonel. However, Ms. Mari's Navi is attacked by a Nebula Navi disguised as MegaMan in a plot to turn NumberMan and MegaMan against each other. Fortunately, the evil plot was foiled after the two caught up with the plan and eliminated the fake Navis.
In the anime, Ms. Mari's personality is fleshed out much more than in the games, and shows she has a wide variety of hobbies, including a passion for hot springs that she shares with Tory Froid, cooking, cosplaying, and more. Despite her romantic woes which she often consults Miyu's fortune telling about, her bubbly and cheerful personality actually gains the attention of most men she meets, attracting Mr. Higsby and Maysa, who become romantic rivals for her affection, as well as others like Noboru Sunayama and Charlie Airstar, although she ignores the former two and flatly rejects the latter two. Ironically, she comes to fall in love with Maysa's later ego Commander Beef.
In episode 43 of MegaMan NT Warrior Axess, Ms. Mari reveals that during childhood, she lost her sister as a result of a unique plane incident. It occurred whilst her family decided to move to a new house, everything was ready but Ms. Mari developed a fever, which caused her mother to stay behind and take care of her. Even so, her father and sister went ahead and boarded the plane, which collided with a falling meteorite whilst airborne over the ocean. No sign of the plane was ever found, which lead Ms. Mari to believe that the familiar woman she keeps seeing, is not her sister. Ultimately, she is properly united with Ms. Yuri during Rockman.EXE Stream.
- According to Ms. Yuri, Ms. Mari's measurements are 33-22-33, which is one of the questions of the quiz in the Power Plant. As Yuri and Mari are twins, they probably have the same measurements.
- Ms. Mari frequently visits Miyu's shop to gain fortune-telling insight on love.
- In Mega Man Battle Network, Ms. Mari says "You lost? That won't do..." if MegaMan gets deleted during the tutorial.