|Johto Number|| 169
|Weight||8.8 lbs. (4.0kg)|
|Gender distribution||50% Male, 50% Female|
|Ability||Shell Armor/Skill Link|
|First Appearance||Pokémon Red and Blue|
The name "Shellder" originates from the word "shell" and possibly "shelter", as Shellder protects itself by hiding in its shell. Shellder is based on the clam. It is a bivalve Pokémon that loves to spit in its foes' faces during battles. Its semi-exclusive attack Clamp can damage foes multiple times and prevent them from escaping.
Shellder is a cheeky Pokémon; it constantly pokes its tongue out at anybody, whether friend or foe. It will also spit on foes. This tends to antagonize enemies into a rage.
Its shell is very strong, apparently harder than a diamond, though only made of a single, smooth layer; unlike Cloyster, who has a thick, rugged and multi-layered shell. Shellder becomes vulnerable when the enemy can attack its insides.
When not protecting itself in battle, it will attack by squirting water at the foe. As a last resort, it will clamp the foe with its powerful shell. However, this leaves Shellder vulnerable to an attack, hence, it is rarely used. As a total last resort, Shellder may use Selfdestruct or Explosion to knock itself and the enemy out.
Shellder travels by rapidly opening and closing its shell, propelling it in the opposite direction of its shell through the water. Shellder are incapable of travel on land, unless in a Pokeball.
Just like an oyster, Shellder can produce pearls with its shell. When a grain of sand enters its shell, it mixes with body fluids to produce the perfectly round pearl.
Despite its thick shell, Shellder will also protect itself at night by sleeping under sand; it burrows into sand with its broad tongue. Shellder sleeps with its large tongue hanging out of its shell. This is likely the reason why it burrows before rest, as its tongue is vulnerable to attack.
Shellder is integral to the evolution of Slowpoke, as is the body part of Slowpoke to which Shellder bites on: its tail. Once Shellder bites the Slowpoke's tail, the two will evolve into a single Pokémon, Slowbro. If Shellder instead attaches itself to Slowpoke's head, it will create Slowking, a notably smarter Pokémon than the other two. This evolution can be reversed if Shellder falls off Slowbro's tail or Slowking's head (this has never happened in video games, though it is possible outside the games and in the anime). This likely won't happen purposely (in the video games at least), as the evolution benefits both Pokémon: Slowpoke can now walk on its hind legs and Shellder can eat the scraps of the Slowpoke. The newly attached Shellder looks very different from its previous purple form, though the new appearance could be a result of a simultaneous metamorphosis in conjunction with Slowpoke. This can also be an example of natural mutualism, a process in which a parasite attaches to a living thing, but benefits for both species (In this case, the Shellder is the parasite).
Shellder is available in most of the Pokémon RPG games, usually by fishing. Shellder is not available for capture in Pokémon Ruby and Sapphire or Pokémon LeafGreen. Shellder can be caught in "Pokémon FireRed" and snagged in Pokémon XD: Gale of Darkness.
All of Cloyster's moves must be learned while in the Shellder stage, with the exception of Spike Cannon. If Shellder is evolved with the Water Stone too early, it will no longer learn any of its level-up attacks.
Shellder is featured in an early episode where one becomes sick and requires Ash to bring forth his medicine... from the other side of a seemingly endless bridge. Incidentally, a Cloyster is also featured in this episode.
Shellder is also featured in the episode "The Evolution Solution", where it is shown to be the way that Slowpoke evolve into Slowbro. Jessie catches a Shellder in this episode, but it bites onto the tail of Professor Westwood's Slowpoke and evolves into Slowbro.
Shellder are also in "A Crowning Achievement", where a Slowpoke habitat starts to run out of room and needs a Slowking to open up a new home, according to an ancient tablet. However, Shellder make all the Slowpoke evolve into Slowbro before the protagonists are able to get the King's Rock. Fortunately, Ash's Larvitar allows a Slowpoke to reach the rock.
Trading Card Game
Shellder rarely appears in the Pokémon Trading Card Game. It has appeared in the following sets:
- Gym Heroes as Misty's Shellder
- EX Fire Red & Leaf Green
- The following games and their instruction manuals: Pokémon Red, Green, and Blue; Pokémon Yellow; Pokémon Stadium and Pokémon Stadium 2; Pokémon Gold, Silver, and Crystal; Pokémon Ruby, Sapphire, and Emerald; Pokémon FireRed and LeafGreen; Pokémon Colosseum and Pokémon XD: Gale of Darkness
- Barbo, Maria. The Official Pokémon Handbook. Scholastic Publishing, 1999. ISBN 0-439-15404-9.
- Loe, Casey, ed. Pokémon Special Pikachu Edition Official Perfect Guide. Sunnydale, CA: Empire 21 Publishing, 1999. ISBN 1-930206-15-1.
- Nintendo Power. Official Nintendo Pokémon FireRed & Pokémon LeafGreen Player’s Guide. Nintendo of America Inc., August 2004. ISBN 1-930206-50-X
- Mylonas, Eric. Pokémon Pokédex Collector’s Edition: Prima’s Official Pokémon Guide. Prima Games, September 21 2004. ISBN 0-7615-4761-4
- Nintendo Power. Official Nintendo Pokémon Emerald Version Player’s Guide. Nintendo of America Inc., April 2005. ISBN 1-930206-58-5