Mitzi/Comics

Season 1
Mitzi makes her debut in Issue 4 in a flashback as Bloom recounts the day where she discovered her fairy powers and met Stella to her new friends, the Winx Club.

After being given a bike by her parents, Mike and Vanessa, Bloom decides to take a walk with Kiko through the streets of Gardenia. She is quickly stopped by Mitzi by her front gates and Mitzi wastes no time taunting Bloom over her new bike and bragging about her new scooter. Bloom tries to ignore Mitzi by walking away but Mitzi continues to taunt her by telling her to just keep pedaling on her bike as she will only be able to chase after her scooter at this rate. Though Bloom tries to brush off Mitzi's words, she realizes that she is right about one thing: that all of her friends have scooters except for her.

Season 4
Mitzi finally makes a physical appearance in Issue 101 where she is enjoying a stroll through the city of Magnolia with her friends Stacy and Brooke.

The three girls revel in all the attention they have been getting so much that Mitzi declares Magnolia to be a paradise where they do not have to deal with the Winx stealing all the attention with their "stupid tricks." However, just as Mitzi and Brooke begin to think that they will not be seeing the Winx for a long time, Stacy finds a poster advertising a Winx Concert in the city later that day. Just seeing the poster causes Mitzi to fly into a rage, yanking the poster off and ripping it to shreds as her friends try to calm her down. She tries to calm herself down to avoid embarrassing herself but is disgusted by these sudden feelings of serenity that she is getting. It turns out to be coming from some music that the trio overhear, so Mitzi drags Stacy and Brooke off to find its source.

The music leads the girls to a park in the middle of Magnolia, where they find a band of native musicians putting on a show. While Brooke and Stacy fall for the band's music and quickly become interested in their instruments, Mitzi comes up with the idea to steal them as she believes them to be either magical or bewitched. Seeing just how much the audience enjoys the band's performance, Stacy and Brooke begin to get on board with Mitzi's plan and Mitzi explains that with the stolen instruments, they should be able to beat Bloom and the Winx on their own turf. While her friends find her plan to be ludicrous, they eventually join in and the three form a band.

That night, Jason leads the Winx over to a dressing room where the band competing against them are resting up. As he explains that the band consists of three young girls around the Winx's age that specialize in traditional instruments, Mitzi, Brooke and Stacy step out to announce themselves as the Sweet Dreams, much to the Winx's dismay. The three quickly taunt the Winx before their performance and, much to the Winx's surprise, the Sweet Dreams are actually competent musicians that the crowd seems to adore. While Flora maintains her calm and compromising nature by claiming that they should be congratulating Mitzi and her friends on their newfound gifts, Stella believes that something is not right as even they had to put in years of practice to become the stars they are today. As the group tries to figure out the cause of the Sweet Dreams' suddenly gained talents, the native musicians from earlier in the day, Djalu, Kerrianne and Mandawuy, or the Aboriginal Soul, rush into the backstage area to tell the Winx to put a stop to the Sweet Dreams' performance.

It turns out that Mitzi, Stacy and Brooke had stolen their instruments, instruments that have been used within Aboriginal tribes for generations to enter a harmonious union with the vital essences of nature, and if such instruments are not played by the tribes who have a right to play them, then the spirits of nature become rebellious. Unfortunately, once the Winx learn all of this, the Sweet Dreams accidentally unleash the spirits of Bunyip and Ngalyod.

As everyone flees the stadium from the rampaging spirits, the Sweet Dreams remain on-stage and wonder why the audience is leaving when their concert has not ended yet. Mitzi then begins to throw a fit and accuses the Winx of unleashing the two spirits to ruin their chances of success until Bunyip smashes his fists onto the stage, putting Mitzi in danger. Bloom and Musa come to Mitzi's rescue but Mitzi is anything but grateful, even after Musa shields her from Ngalyod's fiery breath with her Sonic Screen.

Mitzi appears again just to ridicule Bloom for being so incompetent after the Winx's strongest Convergence fails to affect the two ancient spirits. However, this causes Tecna to realize that the negative energy released by Mitzi and her friends nullifies their Believix powers and Bloom gets the idea to take back the didgeridoo so that Djalu can pacify Bunyip and Ngalyod. While having the didgeridoo taken away from her, Mitzi demands for it to be given back and shouts at Bloom over how much she hates her when she scolds her like a child.

Once everything has been resolved, Mitzi, Brooke and Stacy are forced to work as servers to everyone in the stands to pay for all the damages. The security guard insists that there is a bright side to their situation as they get to enjoy a Winx Band Concert for free, but this only makes Mitzi's mood worse and she pleads for someone to wake her up from such a nightmare.

Season 5
Mitzi makes her first appearance in Issue 118 as one of the audience members to the Jenny Joy Show.

Having heard enough praise being directed at Bloom, Mitzi dismisses all of it to be nothing but "stupid chatter" and declares that she would like to see how Bloom would get by without the use of her magic. She then challenges Bloom in front of everyone—one where she cannot use her "stupid tricks"—and asks if she is going to accept her terms or chicken out. Naturally, Bloom accepts and Mitzi reveals that the challenge will be a cooking competition that will go down in three day's time. As the show's host, Jenny Joy, excitedly declares their competition to be a "spaghetti grudge match," Mitzi storms off the stands and onto the stage to tell Bloom to prepare to look like a total fool. Bloom insists that she can beat Mitzi using just one hand and no magic and Mitzi finalizes the bet by adding that Bloom must relinquish her powers if she were to lose. This does not deter Bloom from taking on the challenge but later that night, Bloom laments over accepting such a challenge all because Mitzi never stops getting on her nerves.

Soon, the day of the Cooking Competition arrives where both Mitzi and Bloom are tasked with creating three dishes under specified timeframes for the three judges. Mitzi remains as competitive as ever during the Competition and earns a score of 24 points, putting her 2 points ahead of Bloom. Unfortunately, the Competition is interrupted when Bloom uncovers that the Trix have snuck in to sabotage her chances of winning and, once they are dealt with, the second round is removed thanks to the damages.

Mitzi ultimately loses to Bloom in the last round and she and Bloom decide to finally put aside their petty rivalry, even if Mitzi is more reluctantly to do so.