Tracey owns a Marill, which debuted in The Crystal Onix, thus also marking the species' main series debut. It was friendly and had a nurturing instinct.
Lyra owns a Marill, which debuted in An Egg Scramble!. It was her main Pokémon.
A Marill with the ability to Sing debuted in Pikachu's Exploration Club. It also reappeared in Pikachu's Ice Adventure, Pikachu's Big Sparking Search, and Pikachu's Big Mysterious Adventure. This Marill would frequently sing, causing Meowth and Team Rocket's other Pokémon to go to sleep, which would make it angry and puff up, much like Jigglypuff's role.
Marill debuted in Pikachu's Vacation. It was causing trouble for Pikachu and his friends at the Pokémon Theme Park along with a Raichu, a Snubbull, and a Cubone.
A Marill appeared in For Crying Out Loud, under the ownership of Wilhomena. This one was a bit of a crybaby and it got lost in a forest with Misty. It reappeared in a flashback in the Japanese version of Gotta Catch Ya Later!.
A Marill appeared in Right on, Rhydon, under the ownership of Pietra. She used it to battle and ultimately catch a Rhydon that knew Surf in order to help her with her digging project.
Lola has a Marill, which she used against Flint's Golem in a battle for the title of Gym Leader of the Pewter Gym in A Family That Battles Together Stays Together!. It won after using the waves of the water to Surf against Golem. It reappeared in a fantasy in Grating Spaces!.
Vivi Winstrate owns a Marill. When Vivi battled Max in Candid Camerupt, Max wanted to go easy on Vivi's Marill, but Ash's Corphish refused to abide with Max and defeated Marill anyway.
A Marill appeared in Three Sides to Every Story!, under the ownership of Lulu. Piplup and an Elekid both fell in love with it, and Elekid ultimately was the one who got its attention.
A Marill appeared in The Power of Us, where it was among the Pokémon following Harriet around.
A Marill appeared in Misty's fantasy in Bye Bye Psyduck.
A Marill appeared in Tricks of the Trade as one of the Pokémon seen at the Pokémon Swap Meet in Palmpona.
Five Marill appeared in The Fire-ing Squad!, where they were among the Pokémon competing in the Fire and Rescue Grand Prix.
A Marill appeared in a fantasy in The Totodile Duel.
A Marill appeared in Love, Totodile Style, under the ownership of Trixie. It is among the Pokémon she uses in her circus.
A Trainer's Marill appeared in Hook, Line, and Stinker, where it was used in the annual Seaking Catching Competition.
Two Marill appeared in Beauty and the Breeder, under the ownership of two different Pokémon Breeders. They participated in a Pokémon breeding competition, with one of them being the first entrant.
A Trainer's Marill appeared in Around the Whirlpool. As part of his Breeder training, Brock approached them for advice.
A Trainer's Marill appeared in Octillery The Outcast and Dueling Heroes as one of the Pokémon participating in the Whirl Cup.
A Marill appeared in Team Rocket's fantasy in Nice Pryce Baby.
Several Marill were among the Pokémon seen at Professor Oak's Laboratory in Journey to the Starting Line!.
A Marill appeared in A Ruin with a View.
A Coordinator's Marill appeared in All Things Bright and Beautifly!.
A Marill was used by one of the students of the Pokémon Trainers' School in Gonna Rule The School!.
A Marill appeared in Abandon Ship! as a resident of the Abandoned Ship. It was seen bouncing past the group with two Azurill.
A Coordinator's Marill appeared in Pros and Con Artists.
A Coordinator's Marill appeared in Disguise Da Limit.
A Marill appeared in A Double Dilemma as a resident of North Petalburg.
A Marill appeared in Lights, Camerupt, Action! as an actor in one of Elijah's movies.
A Coordinator's Marill appeared in Mean With Envy.
A Marill appeared in The Ribbon Cup Caper at the S.S. St. Flower's Pokémon Center.
A Coordinator's Marill appeared in Hi Ho Silver Wind! and Deceit and Assist, where it participated in the Hoenn Grand Festival.
A Marill appeared in a fantasy in The Right Place and the Right Mime.
A Coordinator's Marill appeared in The Saffron Con, where it was competing in the Saffron Contest.
A Marill appeared in Weekend Warrior.
A Marill appeared in On Olden Pond as a resident of an old lake.
A Trainer's Marill appeared in Curbing the Crimson Tide!.
A Coordinator's Marill appeared in What I Did for Love!.
A Marill appeared in New Plot, Odd Lot!, under the ownership of a Coordinator competing in the Mulberry Contest.
A Marill, along with an Azurill and Azumarill, made a cameo in the beginning of Pokémon Ranger and the Temple of the Sea, under the control of Solana's Capture Styler. They were used to put out a fire in a forest while Solana rescued a Sentret.
A Marill appeared in The Rise of Darkrai, along with an Azumarill and Azurill.
A Marill briefly appeared in Pruning a Passel of Pals!, under the ownership of a Coordinator competing in the Wallace Cup.
A Marill appeared in One Team, Two Team, Red Team, Blue Team!.
A Marill appeared in Another One Gabites the Dust!, where it was seen participating in the Performance Stage of the Chocovine Contest.
A Marill appeared in Sticking With Who You Know!.
A Marill appeared in The Fleeing Tower of Sunyshore!, where it was one of the Pokémon seen at the Sunyshore City Pokémon Center.
A Marill made a brief appearance in Coming Full-Festival Circle!. It was among the Pokémon listening to Nando as he played his music.
A Marill made a very brief appearance in League Unleashed!, under the ownership of a boy.
A Marill appeared alongside an Azurill and Azumarill in Zoroark: Master of Illusions.
A Trainer's Marill appeared in Curtain Up, Unova League! and Lost at the League!.
A Marill appeared in Mewtwo — Prologue to Awakening.
Marill has made cameo appearances in Kalos, Where Dreams and Adventures Begin!, A Blustery Santalune Gym Battle!, Awakening the Sleeping Giant, Going for the Gold!, A Battle by Any Other Name!, The Bonds of Evolution!, Heroes - Friends and Faux Alike!, Dreaming a Performer's Dream!, and A Fashionable Battle!.
A Marill appeared in Lumiose City Pursuit!, Mega-Mega Meowth Madness!, Day Three Blockbusters!, Battling With a Clean Slate! and even in a flashback in Mega Evolution Special I, and Garchomp's Mega Bond! at Professor Sycamore's lab.
Two Marill appeared in A Jolting Switcheroo!.
A Marill appeared in a flashback or a fantasy in The Forest Champion!.
A Trainer's Marill appeared in Foggy Pokémon Orienteering!.
A Marill appeared in A Showcase Debut!, under the ownership of a Pokémon Performer participating in the Coumarine City Pokémon Showcase.
A Trainer's Marill appeared in a video in Rivals: Today and Tomorrow!.
A Marill appeared in Hoopa — The Mischief Pokémon.
A Trainer's Marill appeared in Performing with Fiery Charm!.
Four Marill appeared in Pikachu and the Pokémon Music Squad. They were among the Pokémon residing in a forest.
A Trainer's Marill appeared in Adventures in Running Errands!, where Chespin saw it riding on a bike with its Trainer while falling in love, but then Bunnelby grabs its paw while chasing Marill and its Trainer.
A Trainer's Marill appeared in A Performance Pop Quiz!.
A Marill appeared in Mega Evolution Special IV.
Two Marill appeared in The Legend of the Ninja Hero! as residents of the Ninja Village.
A Marill appeared in Party Dancecapades!, under the ownership of a Pokémon Performer attending Monsieur Pierre's dance party.
A Trainer's Marill appeared in Master Class is in Session!.
A wild Marill appeared in Volcanion and the Mechanical Marvel, where it was one of the Pokémon residing at Nebel Plateau.
A Marill appeared in Valuable Experience for All!, under the ownership of a Trainer.
A Marill appeared during a flashback in The Legend of X, Y, and Z!.
Two Trainers' Marill appeared in The Power of Us.
A Trainer's Marill appeared in Turning the Other Mask!.
| Original series entries continue below.
|| Ash's Pokédex
|| Marill, the Water Mouse Pokémon. Its sensitive ears can detect distant sounds and the round rubbery tip on its tail can expand and contract, assisting Marill in the water.
| This concludes the entries from the original series.
|| Dawn's Pokédex
|| Marill, the Aqua Mouse Pokémon. The tip of its tail floats in water, so it can swim in any current no matter how rough.
|| Dawn's Pokédex
|| Marill, the Aqua Mouse Pokémon. Its floating tail allows it to remain steady against the strongest of water currents.
| This concludes the entries from the Diamond & Pearl series.