Nothing about Cloyster screams competitive powerhouse, and that's fine. Water/Ice means only weak to Electric, Grass, Fighting, and Rock. An original Gen 1 pick. Needs some investment to avoid getting outsped.
Defense leads and Sp. Def gets almost nothing. That's Cloyster's stat line in a nutshell. 3 stats sit in respectable range, but the spread is brutal. Moderately hard to find and yields 2 Defense EVs.
It fights by keeping its shell tightly shut for protection and by shooting spikes to repel foes.
Cloyster Weakness
VulnerableCloyster's Water/Ice typing leaves it vulnerable to Electric, Grass, Fighting, and Rock moves. Cloyster's physical bulk (base 180 Def) helps cushion physical weakness hits, but special attackers are the bigger threat.
- Fairy type does not exist — Dragon has fewer checks
- Physical / Special split now per-move (introduced Gen IV)
Getting Cloyster requires an evolution item, not just grinding levels. The chain starts at Shellder. Breed this form to get Shellder eggs (average hatch time). Defense grew the most through evolution (+80 over Shellder), and Cloyster peaks at 525 total stats.
How to Evolve
Breed with Cloyster to get Shellder eggs easily using 25 partners from the Water3 egg group. Notable egg moves include Aqua Ring, Avalanche, Barrier and 9 more.
Best Build
No build content available for this Pokemon in Gen 5.
Try selecting a different game/generation filter, or check back later.
You'll want to breed for Aqua Ring and Avalanche on Cloyster. These egg moves aren't just nice to have. Combined with STAB from Blizzard and Hydro Pump, they expand what Cloyster can actually threaten in practice.
Level-Up Moves
TM Moves
Egg Moves
Tutor Moves
Reminder Moves
Transfer Moves
Cloyster tops out at moderate rates across 6 locations in late-game fishing spots. The encounters below are sorted by rate so you can see exactly what you're working with.
Where To Catch Cloyster in Black & White
To get Cloyster, start by catching Shellder through fishing encounters at Lv. 35-70. The chain covers 2 catchable stages before reaching the final form.
Step 1Catch ShellderEASYRoute 13BlackSuper RodLv.35-60CommonLateRouteAnyShaking spotEASYRoute 13BlackSuper RodLv.35-55CommonLateRouteAnyEASYRoute 13WhiteSuper RodLv.35-60CommonLateRouteAnyShaking spotEASYRoute 13WhiteSuper RodLv.35-55CommonLateRouteAnyEASYUndella BayWhiteSuper RodLv.35-60CommonLateWaterAnyShaking spotEASYUndella BayWhiteSuper RodLv.35-55CommonLateWaterAnyEASYUndella BayBlackSuper RodLv.35-60CommonLateWaterAnyShaking spotEASYUndella BayBlackSuper RodLv.35-55CommonLateWaterAnyEASYUndella TownWhiteSuper RodLv.35-60CommonLateCityAnyShaking spotEASYUndella TownWhiteSuper RodLv.35-55CommonLateCityAnyEASYUndella TownBlackSuper RodLv.35-60CommonLateCityAnyShaking spotEASYUndella TownBlackSuper RodLv.35-55CommonLateCityAny
Step 2Cloyster ✓EXTREMERoute 13BlackSuper RodLv.45-70RareLateRouteAnyShaking spotEXTREMERoute 13WhiteSuper RodLv.45-70RareLateRouteAnyShaking spotEXTREMEUndella BayBlackSuper RodLv.45-70RareLateWaterAnyShaking spotEXTREMEUndella BayWhiteSuper RodLv.45-70RareLateWaterAnyShaking spotEXTREMEUndella TownWhiteSuper RodLv.45-70RareLateCityAnyShaking spotEXTREMEUndella TownBlackSuper RodLv.45-70RareLateCityAnyShaking spotor evolve from Shellder (Step 1)
We rate Cloyster C-Tier — a situational pick that fills a niche. At 525 BST, the stats are spread pretty evenly. Base 180 Defense stands out.
Shellder evolves into Cloyster using a Water Stone. Cloyster is the fully evolved form. At 525 BST, it's got solid stats to work with.
Shell Armor protects against critical hits — that's the one you want on Cloyster. Overcoat is the hidden ability. Niche, but it has its uses. Skill Link works too if your team needs something different.
Base 70 Speed is workable — faster than some, slower than many. On offense, Cloyster is a mixed attacker — base 95 Attack and 85 Sp. Atk. Defensively? Enough bulk to take a hit or two.
Cloyster appears in 20 games, including Yellow, Red & Blue, and Gold & Silver.
One of the original 151, Cloyster has appeared in 20 games — nearly every mainline game. From Red & Blue through the latest titles, it's rarely been left out of a regional Pokedex.
- Gen IY
Yellow - Gen IRBDebut

Red & Blue - Gen IIGS

Gold & Silver - Gen IIC
Crystal - Gen IIIRS

Ruby & Sapphire - Gen IIIFRLG

FireRed & LeafGreen - Gen IIIE
Emerald - Gen IVPt
Platinum - Gen IVHGSS

HeartGold & SoulSilver - Gen IVDP

Diamond & Pearl - Gen VBW

Black & White - Gen VB2W2

Black 2 & White 2 - Gen VIXY

X & Y - Gen VIORAS

Omega Ruby & Alpha Sapphire - Gen VIIUSUM

Ultra Sun & Ultra Moon - Gen VIISM

Sun & Moon - Gen VIILGPE

Let's Go Pikachu & Eevee - Gen VIIISwSh

Sword & Shield - Gen VIIIPLA
Legends: Arceus - Gen VIIIBDSP

Brilliant Diamond & Shining Pearl - Gen IXSV

Scarlet & Violet - Gen IXLZA
Legends: Z-A