Clamperl

Generation III introduced Clamperl in Pokémon Ruby and Pokémon Sapphire as a marine creature inspired by a clam or an oyster. Its heavy, sturdy blue shell protects it, but it also works as a trap: it clamps both halves of the shell down on its prey and does not release it until it stops moving. Its rounded appearance and the pearl peeking out between the shells make it seem harmless, although the Pokédex entries make it clear that it is carnivorous.

It produces a single pearl during its lifetime. That item amplifies psychic powers and is worth far more than the pearls produced by Shellder. The shell develops nicks and scratches when it reaches its maximum size; furthermore, if its body no longer fits inside, evolution is near.

Clamperl is the basic stage of a line with two possible destinations. Trading it while it holds a Deep Sea Tooth evolves it into Huntail, while a Deep Sea Scale leads to Gorebyss. The choice of item determines which form it takes and which marine traits it develops afterwards.

Clamperl does not have standout overall competitive performance, but it does have one very specific combination: 74 Special Attack, access to Shell Smash at Lv.50, and a Speed stat of 32 that appreciates any boost. Its 85 Defense is its best defensive figure, although its 35 HP and 55 Special Defense make it difficult to find a safe turn to set up.

Shell Armor is the most reliable ability: it blocks critical hits and prevents a lucky roll from bringing down a defensive strategy. Rattled, its Hidden Ability, raises its Speed when it is hit by Dark-, Ghost-, or Bug-type attacks, but it does not solve its durability problems or replace a stat boost.

Its Water typing gives it STAB on Surf, Water Pulse, and Brine. It can also punish Fire-, Ground-, and Rock-type Pokémon, while Ice Beam expands its coverage against targets vulnerable to Ice. Defensively, it resists Fire, Water, Ice, and Steel, but Electric- and Grass-type attacks deal heavy damage to it.

In a normal playthrough, it works best as a mid-game special attacker, when the opponent has already lost some of its answers to Water. Shell Smash can turn it into an immediate threat, but it lowers its defenses and leaves its initial Speed exposed. Fast opponents, priority attacks, and Grass- or Water-type Pokémon that can take its coverage stop the plan. Its offensive movepool is useful, although fairly limited.

Clamperl belongs to the Water 1 Egg Group and has a 50% gender ratio for each sex. Its Eggs require 20 cycles, equivalent to approximately 5355 steps using the usual formula. Hatching them is not especially quick, so preparing several specimens takes some patience.

Its notable Egg Moves include Body Slam, which makes use of its 64 Attack, and Muddy Water, whose power of 90 fits its 74 Special Attack better. Supersonic and Confuse Ray provide disruption, while Aqua Ring offers gradual recovery. The choice depends on whether direct damage or a more awkward role for the opponent is desired.

To obtain Huntail, Clamperl must be traded while holding a Deep Sea Tooth. To obtain Gorebyss, it must be traded while holding a Deep Sea Scale. Leveling it up or using a stone is not enough: the trade and the specific item determine the evolution.

It lives in the sea and has a catch rate of 255, so it is easy to catch. Its only effort gain is 1 Defense. The items it can hold in the wild are Blue Shard, Pearl, and Big Pearl.