Zoey used Misdreavus in Jubilife City Contest before Dawn's turn. Misdreavus performed on the appeal stage of the contest and Misdreavus used Double Team. It then used Confuse Ray to send the illusions away and used Shock Wave to display its power. Its appeal allowed Zoey to advance to the battle rounds.
Misdreavus later appeared with Glameow to warn Ash, Dawn and Brock that Zoey was in trouble, as she got hurt. She arrived to Hearthome City, with Glameow and her newly caught Shellos, to participate in a Contest. Misdreavus was briefly seen during the Wallace Cup, defeating a Mothim, thus allowing Zoey to advance further in the competition.
Before the Sinnoh Grand Festival, Zoey had Misdreavus evolve into Mismagius using a Dusk Stone and learn some new moves. It battled with Zoey's Leafeon against Nando's Kricketune and Lopunny. Mismagius and Leafeon were put at an early disadvantage due to Kricketune's singing with Lopunny's dancing. However, Mismagius helped Zoey make a comeback with a Double Team trick and using Lucky Chant to counter Kricketune's Sing. At the end of the performance, Mismagius used Psywave to boost Leafeon and the incredible combination was enough to allow Zoey to advance to next round.
During the semi-final round, Nando sent Kricketune and Lopunny to battle Zoey's Mismagius and Leafeon. Zoey's Leafeon started off with Energy Ball, with Mismagius using Thunder Wave. Lopunny deflected their attacks with Jump Kick, whereas Kricketune's Bug Buzz weakened Leafeon. Lopunny danced around, powered by the Bug Buzz, which deflected Zoey's Pokémon's attacks. Zoey had Mismagius and Leafeon use Double Team, surrounding Nando's Pokémon. While Lopunny's Blizzard banished their illusions, this move caused Zoey's Pokémon to be in the spotlight.
Kricketune used Sing, to which Mismagius' Lucky Chant negated its effects. Lopunny went to use Focus Blast, which was countered with Leafeon's Leaf Blade. Kricketune went to use X-Scissor, whereas Mismagius launched Psywave. Lopunny took Kricketune away to evade Psywave and launched it, only for Kricketune to collide with Leafeon's Leaf Blade. Next, Kricketune used Silver Wind, which combined with Lopunny's Blizzard, turning the combo attack into snowflakes. Leafeon used Aerial Ace, powered with Mismagius' Psywave, making Leafeon look as it had wings. Lopunny went to intercept Leafeon, but was struck by Mismagius' Thunder Wave. Kricketune used X-Scissor and collided with Leafeon. When time was up, Nando lost more points than Zoey did, and the latter won the round.