Misty is one of Pokémon's most enduring and beloved characters. She's Ash's longest-serving female companion known for her explosive behavior, tendency to pick fights with him, and, of course, her love for Water-type Pokémon. In the games, she also serves as the second challenge players must face in Kanto.
As the Cerulean City Gym Leader, Misty represents a moderate threat. She isn't one of the most arduous Gym Leaders in the franchise but still poses a challenge, especially to inexperienced trainers. Throughout her many appearances across the games, she usually has between two and four Pokémon, and Starmie is always her ace. And even though her battle is no walk in the park, there are strategies to make things easier.
Preparing For The Battle
Players know that, before challenging any Gym, it's vital to have their Pokémon team in prime shape. Every player should pay a visit to the Pokémon Center and heal their entire party. Stocking up in healing items is also advisable, especially Potions and Super Potions, which will prevent constant returns to the Pokémon Center.
Because Misty is the second Leader in the Kanto games, she doesn't heal any of her Pokémon during battle. However, she can use another item to enhance her team.
Pokémon Levels
In the original Red & Green and Yellow, Misty's Pokémon - Staryu and Starmie - are levels 18 and 21, respectively. Her team remains the same in the Gen III remakes, FireRed & LeafGreen, but changes in Gen VII's Let's Go games. Instead of Staryu, she has a level 18 Psyduck, and her Starmie descends to level 19. Players challenging her gym should have their Pokémon at level 18, at least.
In Gen II's Gold, Silver & Crystal, Misty has four Pokémon, two at level 42, one at level 44, and her ace at level 47. In HeartGold & SoulSilver, she has the same team but at higher levels. Her weakest is level 49, and her Starmie is level 54 and holds a Sitrus Berry.
If You Chose Bulbasaur, It's A Walk In The Park
As fans know, Grass Pokémon are Super Effective against Water-types. In the Kanto Games, choosing Bulbasaur gives players a type advantage against the first two Gym Leaders, Rock-type specialist Brock and Misty. In contrast, choosing Charmander gives them a type disadvantage, with Fire being weak to both Rock and Water.
Bulbasaur is a dual-type Grass/Poison Pokémon that learns Vine Whip at level 13 in Gen I, level 10 in Gen III, and level 9 in Gen VII. Starmie is a dual Water/Psychic-type, making it Super Effective against Bulbasaur's Poison. However, it doesn't know any Psychic move in Gens I and III. It does in Gen VII though, which can be problematic, but Bulbasaur evolves into Ivysaur at level 16. Furthermore, it learns Razor Leaf at Level 20, giving it a powerful Grass attack to counter.
If You Chose Squirtle, Don't Use Its Water Moves
Squirtle will give players an advantage against Brock's Gym, but it will be neutral against Misty's. Like Bulbasaur, Squirtle evolves into Wartortle at level 16 but doesn't learn any convenient moves in Gen I until level 24. In Gen III, Wartortle learns the handy move Bite at level 19, and in Gen VII at level 17.
Players who chose Squirtle might prefer using it only against Staryu, or not at all. They could win the battle with the water turtle, but it would be necessarily complicated.
If You Chose Charmander, Make Sure To Catch A Grass Or Electric-Type
Using Charmander in this battle would be fatal. Players who chose the fire salamander should catch a Grass-type at once to make Misty's battle more manageable. Plenty of level 13+ Oddish and Bellsprout inhabit Route 5, two Pokémon that eventually evolve into the very decent Vileplume and Victreebel.
Players can also catch Pikachu in Viridian Forest, although the electric mouse has only a 5% chance of spawning. Still, after some searching, the cute yellow mouse will surely emerge. Several other Pokémon can also be helpful against Misty, like Jigglypuff, Clefairy, Mankey, or even Rattata.
For Staryu, Stick With Basic Attacks
Misty always opens with Staryu, a level 18 pure Water-type that only knows two moves in Gen I. In the remakes, it has a complete moveset of four, making it more of a threat. In Generation I, Tackle and Water Gun will do nothing to a Grass or Electric Pokémon.
In Generation III, Misty uses Staryu to stall, and it has two annoying moves, Harden and Recover. It's best to defeat this Pokémon as quickly as possible, or it will unnecessarily draw out the battle by increasing its Defense and regaining health.
For Starmie, Take Out The Big Guns
Misty's ace is always Starmie. The dual Water/Psychic starfish only knows three moves in Generations I and VII but has complete a moveset in the Generation III remakes. In Red & Blue, it knows Tackle, Water Gun, and BubbleBeam, none of which will do a lot of harm to Grass, Electric, or even Normal-types. In Let's Go, it knows Swift, which always goes first, Scald, and Psybeam. The latter is Super Effective against Bulbasaur, Oddish, and Bellsprout, so players should be prepared to take some damage.
In FireRed & LeafGreen, Starmie knows Recover, as well as Swift and Rapid Spin. Its sole Water attack, Water Pulse, has a 20% chance of confusing the target. Starmie should go down with one or two Grass or Electric moves, but its Psychic-type also makes it weak to Bugs, which are abundant in the games' early routes and Viridian Forest.
For Psyduck, Tread Carefully
Misty only uses Psyduck in the Let's Go games. The yellow duck, which comes at level 18, will only know two moves. Confusion will be Super Effective against Bulbasaur, Oddish, and Bellsprout, but a powerful-enough Grass move should take Psyduck down.
If players don't want to take any chances, Pikachu could take down both Psyduck and Starmie. If there are no Grass or Electric types in the team, a Bug-type could also do, but those tend to be quite frail.
Rematch Battles
Starting with HeartGold & SoulSilver, players can rematch Misty after they become Champions. She'll have a complete team of six Pokémon, two of them at level 60. All of them will be pretty straightforward, although her tanky Milotic can be troublesome. Quagsire's dual Water/Ground-type will make it immune to Electric moves but four times weak to Grass. Lanturn loses its Electric weakness, thanks to its dual Water/Electric-type, but makes it vulnerable to Ground.
In Let's Go, players can also have a rematch battle with her, where she only has five Pokémon. Her ace will be Gyarados, a bulky and menacing Pokémon that is four times weak to Electric moves.
Pokémon World Tournament
Misty is a contestant in Generation V's Pokémon World Tournament. Players can battle her in the Kanto Leaders and Type-Experts Tournaments. In the former, she'll have only Gen I Pokémon, including a Blastoise and a Lapras. In the latter, she'll have her Lanturn and Quagsire's from the Gen IV rematch, plus a Jellicent from Gen V.
All of her Pokémon are level 50, per the Tournament's rules, and hold items. Most of them are Berries that raise a particular Stat, but Jellicent notably has the Leftovers, which increase its HP with every turn. Quagsire has the Focus Sash, which prevents it from fainting with one hit.