In the anime
At Porta Vista, Brock, Ash, and Misty were trying to return to the mainland when Misty noticed an injured Horsea near the coast. The little seahorse squirted out a warning in ink that the children didn't understand.
Later, the group learned that a woman named Nastina was trying to build an underwater resort in the local reefs, and that her workers were being attacked by many Tentacool. A strange chain of events lead to the community being attacked by a gigantic Tentacruel, who was angry at the humans demolishing the reef. Horsea and Misty's pleading saved the city, and Horsea then joined Misty's team.
Much later, in The Misty Mermaid, Horsea was feeling ill because Misty wasn't letting it out enough to get any exercise. With no ocean nearby, Misty decided to take it home to Cerulean City, where it could play and swim in her Gym's many aquariums. After participating in a water ballet, Misty left Horsea and her Starmie in the care of her sisters.
Advanced Generation series
In Cerulean Blues Misty was reunited with Horsea and Starmie upon becoming the official Cerulean Gym Leader. Horsea was seen saving Misty from the whirlpool her Gyarados had created. It was also seen being fed Pokémon food by Misty in The Blue Badge of Courage and A Date With Delcatty.
Personality and characteristics
As shown in its debut, Horsea prefers to use words before battling head on as it it tried to explain to the giant Tentacruel that violence wouldn't solve anything. Horsea, like Goldeen, has trouble functioning on land, so Misty didn't use it much in her adventures. However, when it was used, it tended to be very resourceful - using ink to draw pictures or leave trails. It, like the rest of its species, preferred large bodies of water to swim in. However, because of only being able to swim in small puddles of water, it became sad and ill. Luckily, once it was left in the Cerulean Gym with Misty's sisters, and Misty saw how happy it was with the pool's size she decided to leave it there. When Misty returned to the gym in Cerulean Blues, Horsea happily greeted her along with Starmie, but was later scared away by Gyarados.
| Using Smokescreen
| A † shows that the move was used recently, unless all moves fit this case or there are fewer than five known moves.
In the games
Misty's Horsea appears only in Pokémon Stadium Round 1 battle.
In the manga
In the Pokémon Zensho manga
Misty's Horsea appeared in Cerulean City where it was seen in her Gym.
In the TCG
Horsea was featured in the TCG as one of Misty's Pokémon. The following is a list of cards named Misty's Horsea.
For more information on this Pokémon's species, see Horsea.