Goldeen has proved helpful when Misty and her friends need assistance swimming or locating something underwater. In Pokémon Shipwreck, Goldeen tried to find an exit out of the sunken S.S. Anne. Instead, it discovered Team Rocket, who would otherwise have drowned. Goldeen then swam to the surface with her Trainer, while Starmie and Squirtle followed behind with Ash and Brock. It was later sent out to attempt to drag the raft away from James's Gyarados, but they were all caught up in the Dragon Rage and sent flying. It reappeared in Tentacool & Tentacruel, where it helped Staryu and Starmie rescue sailors who had been attacked.
Misty does not use Goldeen very often because it cannot battle or maneuver outside of water. When it was, it often did poorly due to its lack of battle experience. An example of this is a battle against Marina in Bye Bye Psyduck, where it lost to her Tentacruel, before Misty's Staryu took over and won.
In Snack Attack, Goldeen was sent out in an attempt to fight a wild Snorlax, but it was completely helpless and was almost eaten before being recalled.
Goldeen fought Dorian's Qwilfish in Just Add Water, managing to land a Horn Attack after dodging Qwilfish's Tackles with Agility. Goldeen then used Supersonic, but Qwilfish shrugged off its effects and fired Pin Missile. Goldeen managed to reflect those coming its way by spinning its tail. Goldeen aimed a Horn Drill, which Qwilfish dodged. Qwilfish used another Pin Missile, hammering Goldeen from behind. A final Take Down was enough to knock Goldeen out and win the round for Dorian.
Goldeen is shown to be quite strong and fast, often being called upon to transport Misty or others in the water, with a true testament of its strength when rescuing Team Rocket when they were trapped and drowning aboard the St. Anne during Pokémon Shipwreck, taking it upon itself to save them after it came across them.
Goldeen wasn't seen very much throughout the series due to it being a water-bound species, flailing when displaced from it. Goldeen is shown to know a variety of techniques that has helped it defeat other Pokémon, such as Victreebel in The Stun Spore Detour, however, when Goldeen battled other Water-type specialists it faced difficulties as seen when it battled Marina in Bye Bye Psyduck and Dorian in Just Add Water.
Misty's Goldeen Cards listed with a blue background are only legal to use in the current Expanded format. Cards listed with a silver background are legal to use in both the current Standard and Expanded formats.