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#0139 · Generation I

Omastar

Rock / Water · Spiral Pokémon — first seen in Generation I.

Showing the official games. Pick a ROM hack to see how it changes this Pokémon, or compare all of them.

Base stats

StatBaseMinMax
HP70
250344
Attack60
112240
Defense125
229383
Sp. Attack115
211361
Sp. Defense70
130262
Speed55
103229
Total495

Min and max are at level 100: the minimum is 0 IVs, 0 EVs and a hindering nature, the maximum 31 IVs, 252 EVs and a beneficial nature. Shedinja's HP is always 1 whatever the formula says.

Type defences

Damage Omastar takes from each attacking type.

×4
Grass
×2
FightingGroundElectric
×½
NormalFlyingPoisonIce
×¼
Fire
×1
RockBugGhostSteelWaterPsychicDragonDarkFairy

Evolution

Methods are the current official ones. A ROM hack may change them — trade evolutions especially; the guide table below says which do.

In the ROM hacks it evolves differently

Each guide's own line, in the words its creator published.

In Pokémon Odyssey

Evolves into Omastar (Etrian) at Level 40OmastarOmastar

Moves by official game

Level-up, TM/HM, tutor and egg moves exactly as each game has them. The newest game this site covers is open; the rest fold out.

Ultra Sun / Ultra Moon18 level-up · 31 TM/HM · 8 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
—Spike CannonNormalPhysical20100%15
1BiteDarkPhysical60100%25
1Hydro PumpWaterSpecial11080%5
1WithdrawWaterStatus——40
1Spike CannonNormalPhysical20100%15
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Shell SmashNormalStatus——15
75Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM100ConfideNormalStatus——20
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM23Smack DownRockPhysical50100%15
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM48RoundNormalSpecial60100%15
TM55ScaldWaterSpecial80100%15
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM80Rock SlideRockPhysical7590%10
TM87SwaggerNormalStatus—85%15
TM88Sleep TalkNormalStatus——10
TM90SubstituteNormalStatus——10
TM94SurfWaterSpecial90100%15
TM98WaterfallWaterPhysical80100%15

Move tutor

MoveTypeCat.PowerAcc.PP
BindNormalPhysical1585%20
SnoreNormalSpecial50100%15
Icy WindIceSpecial5595%15
Knock OffDarkPhysical65100%20
Iron DefenseSteelStatus——15
Water PulseWaterSpecial60100%20
Earth PowerGroundSpecial90100%10
Stealth RockRockStatus——20
Sun / Moon18 level-up · 31 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
—Spike CannonNormalPhysical20100%15
1BiteDarkPhysical60100%25
1Hydro PumpWaterSpecial11080%5
1WithdrawWaterStatus——40
1Spike CannonNormalPhysical20100%15
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Shell SmashNormalStatus——15
75Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM100ConfideNormalStatus——20
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM23Smack DownRockPhysical50100%15
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM48RoundNormalSpecial60100%15
TM55ScaldWaterSpecial80100%15
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM80Rock SlideRockPhysical7590%10
TM87SwaggerNormalStatus—85%15
TM88Sleep TalkNormalStatus——10
TM90SubstituteNormalStatus——10
TM94SurfWaterSpecial90100%15
TM98WaterfallWaterPhysical80100%15
Omega Ruby / Alpha Sapphire17 level-up · 34 TM/HM · 8 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1Hydro PumpWaterSpecial11080%5
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
40Spike CannonNormalPhysical20100%15
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Shell SmashNormalStatus——15
75Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM100ConfideNormalStatus——20
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM23Smack DownRockPhysical50100%15
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM48RoundNormalSpecial60100%15
TM55ScaldWaterSpecial80100%15
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM80Rock SlideRockPhysical7590%10
TM87SwaggerNormalStatus—85%15
TM88Sleep TalkNormalStatus——10
TM90SubstituteNormalStatus——10
TM94Secret PowerNormalPhysical70100%20
HM03SurfWaterSpecial90100%15
HM05WaterfallWaterPhysical80100%15
HM06Rock SmashFightingPhysical40100%15
HM07DiveWaterPhysical80100%10

Move tutor

MoveTypeCat.PowerAcc.PP
BindNormalPhysical1585%20
SnoreNormalSpecial50100%15
Icy WindIceSpecial5595%15
Knock OffDarkPhysical65100%20
Iron DefenseSteelStatus——15
Water PulseWaterSpecial60100%20
Earth PowerGroundSpecial90100%10
Stealth RockRockStatus——20
X / Y17 level-up · 32 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1Hydro PumpWaterSpecial11080%5
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
40Spike CannonNormalPhysical20100%15
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Shell SmashNormalStatus——15
75Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM100ConfideNormalStatus——20
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM23Smack DownRockPhysical50100%15
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM48RoundNormalSpecial60100%15
TM55ScaldWaterSpecial80100%15
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM80Rock SlideRockPhysical7590%10
TM87SwaggerNormalStatus—85%15
TM88Sleep TalkNormalStatus——10
TM90SubstituteNormalStatus——10
TM94Rock SmashFightingPhysical40100%15
HM03SurfWaterSpecial90100%15
HM05WaterfallWaterPhysical80100%15
Black 2 / White 216 level-up · 31 TM/HM · 8 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
40Spike CannonNormalPhysical20100%15
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Shell SmashNormalStatus——15
75Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM23Smack DownRockPhysical50100%15
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM48RoundNormalSpecial60100%15
TM55ScaldWaterSpecial80100%15
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM80Rock SlideRockPhysical7590%10
TM87SwaggerNormalStatus—85%15
TM90SubstituteNormalStatus——10
TM94Rock SmashFightingPhysical40100%15
HM03SurfWaterSpecial90100%15
HM05WaterfallWaterPhysical80100%15
HM06DiveWaterPhysical80100%10

Move tutor

MoveTypeCat.PowerAcc.PP
BindNormalPhysical1585%20
SnoreNormalSpecial50100%15
Icy WindIceSpecial5595%15
Sleep TalkNormalStatus——10
Knock OffDarkPhysical65100%20
Iron DefenseSteelStatus——15
Earth PowerGroundSpecial90100%10
Stealth RockRockStatus——20
Black / White16 level-up · 31 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
40Spike CannonNormalPhysical20100%15
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Shell SmashNormalStatus——15
75Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM23Smack DownRockPhysical50100%15
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM48RoundNormalSpecial60100%15
TM55ScaldWaterSpecial80100%15
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM80Rock SlideRockPhysical7590%10
TM87SwaggerNormalStatus—85%15
TM90SubstituteNormalStatus——10
TM94Rock SmashFightingPhysical40100%15
HM03SurfWaterSpecial90100%15
HM05WaterfallWaterPhysical80100%15
HM06DiveWaterPhysical80100%10
HeartGold / SoulSilver15 level-up · 37 TM/HM · 9 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
40Spike CannonNormalPhysical20100%15
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM03Water PulseWaterSpecial60100%20
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM43Secret PowerNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM55BrineWaterSpecial65100%10
TM58EndureNormalStatus——10
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM76Stealth RockRockStatus——20
TM78CaptivateNormalStatus—100%20
TM80Rock SlideRockPhysical7590%10
TM82Sleep TalkNormalStatus——10
TM83Natural GiftNormalPhysical—100%15
TM87SwaggerNormalStatus—85%15
TM90SubstituteNormalStatus——10
HM03SurfWaterSpecial90100%15
HM05WhirlpoolWaterSpecial3585%15
HM06Rock SmashFightingPhysical40100%15
HM07WaterfallWaterPhysical80100%15
HM08Rock ClimbNormalPhysical9085%20

Move tutor

MoveTypeCat.PowerAcc.PP
HeadbuttNormalPhysical70100%15
SnoreNormalSpecial50100%15
Icy WindIceSpecial5595%15
RolloutRockPhysical3090%20
Ancient PowerRockSpecial60100%5
Knock OffDarkPhysical65100%20
DiveWaterPhysical80100%10
Iron DefenseSteelStatus——15
Earth PowerGroundSpecial90100%10
Platinum15 level-up · 36 TM/HM · 8 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
40Spike CannonNormalPhysical20100%15
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM03Water PulseWaterSpecial60100%20
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM43Secret PowerNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM55BrineWaterSpecial65100%10
TM58EndureNormalStatus——10
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM76Stealth RockRockStatus——20
TM78CaptivateNormalStatus—100%20
TM80Rock SlideRockPhysical7590%10
TM82Sleep TalkNormalStatus——10
TM83Natural GiftNormalPhysical—100%15
TM87SwaggerNormalStatus—85%15
TM90SubstituteNormalStatus——10
HM03SurfWaterSpecial90100%15
HM06Rock SmashFightingPhysical40100%15
HM07WaterfallWaterPhysical80100%15
HM08Rock ClimbNormalPhysical9085%20

Move tutor

MoveTypeCat.PowerAcc.PP
SnoreNormalSpecial50100%15
Icy WindIceSpecial5595%15
RolloutRockPhysical3090%20
Ancient PowerRockSpecial60100%5
Knock OffDarkPhysical65100%20
DiveWaterPhysical80100%10
Iron DefenseSteelStatus——15
Earth PowerGroundSpecial90100%10
Diamond / Pearl15 level-up · 36 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
7BiteDarkPhysical60100%25
10Water GunWaterSpecial40100%25
16RolloutRockPhysical3090%20
19LeerNormalStatus—100%30
25Mud ShotGroundSpecial5595%15
28BrineWaterSpecial65100%10
34ProtectNormalStatus——10
37Ancient PowerRockSpecial60100%5
40Spike CannonNormalPhysical20100%15
48TickleNormalStatus—100%20
56Rock BlastRockPhysical2590%10
67Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM03Water PulseWaterSpecial60100%20
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM43Secret PowerNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
TM55BrineWaterSpecial65100%10
TM58EndureNormalStatus——10
TM68Giga ImpactNormalPhysical15090%5
TM69Rock PolishRockStatus——20
TM71Stone EdgeRockPhysical10080%5
TM74Gyro BallSteelPhysical—100%5
TM76Stealth RockRockStatus——20
TM78CaptivateNormalStatus—100%20
TM80Rock SlideRockPhysical7590%10
TM82Sleep TalkNormalStatus——10
TM83Natural GiftNormalPhysical—100%15
TM87SwaggerNormalStatus—85%15
TM90SubstituteNormalStatus——10
HM03SurfWaterSpecial90100%15
HM06Rock SmashFightingPhysical40100%15
HM07WaterfallWaterPhysical80100%15
HM08Rock ClimbNormalPhysical9085%20
FireRed / LeafGreen13 level-up · 23 TM/HM · 6 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1Water GunWaterSpecial40100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
13BiteDarkPhysical60100%25
19Water GunWaterSpecial40100%25
25Mud ShotGroundSpecial5595%15
31LeerNormalStatus—100%30
37ProtectNormalStatus——10
40Spike CannonNormalPhysical20100%15
46TickleNormalStatus—100%20
55Ancient PowerRockSpecial60100%5
65Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM03Water PulseWaterSpecial60100%20
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM43Secret PowerNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
HM03SurfWaterSpecial90100%15
HM06Rock SmashFightingPhysical40100%15
HM07WaterfallWaterPhysical80100%15
HM08DiveWaterPhysical80100%10

Move tutor

MoveTypeCat.PowerAcc.PP
Body SlamNormalPhysical85100%15
Double-EdgeNormalPhysical120100%15
Seismic TossFightingPhysical—100%20
MimicNormalStatus——10
Rock SlideRockPhysical7590%10
SubstituteNormalStatus——10
Emerald12 level-up · 23 TM/HM · 12 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
13BiteDarkPhysical60100%25
19Water GunWaterSpecial40100%25
25Mud ShotGroundSpecial5595%15
31LeerNormalStatus—100%30
37ProtectNormalStatus——10
40Spike CannonNormalPhysical20100%15
46TickleNormalStatus—100%20
55Ancient PowerRockSpecial60100%5
65Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM03Water PulseWaterSpecial60100%20
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM43Secret PowerNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
HM03SurfWaterSpecial90100%15
HM06Rock SmashFightingPhysical40100%15
HM07WaterfallWaterPhysical80100%15
HM08DiveWaterPhysical80100%10

Move tutor

MoveTypeCat.PowerAcc.PP
Body SlamNormalPhysical85100%15
Double-EdgeNormalPhysical120100%15
Seismic TossFightingPhysical—100%20
MimicNormalStatus——10
Rock SlideRockPhysical7590%10
SubstituteNormalStatus——10
SnoreNormalSpecial50100%15
Icy WindIceSpecial5595%15
EndureNormalStatus——10
RolloutRockPhysical3090%20
SwaggerNormalStatus—85%15
Sleep TalkNormalStatus——10
Ruby / Sapphire12 level-up · 23 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
13BiteDarkPhysical60100%25
19Water GunWaterSpecial40100%25
25Mud ShotGroundSpecial5595%15
31LeerNormalStatus—100%30
37ProtectNormalStatus——10
40Spike CannonNormalPhysical20100%15
46TickleNormalStatus—100%20
55Ancient PowerRockSpecial60100%5
65Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM03Water PulseWaterSpecial60100%20
TM06ToxicPoisonStatus—90%10
TM07HailIceStatus——10
TM10Hidden PowerNormalSpecial60100%15
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM37SandstormRockStatus——10
TM39Rock TombRockPhysical6095%15
TM42FacadeNormalPhysical70100%20
TM43Secret PowerNormalPhysical70100%20
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
HM03SurfWaterSpecial90100%15
HM06Rock SmashFightingPhysical40100%15
HM07WaterfallWaterPhysical80100%15
HM08DiveWaterPhysical80100%10
Crystal10 level-up · 24 TM/HM · 1 tutor

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
13BiteDarkPhysical60100%25
19Water GunWaterSpecial40100%25
31LeerNormalStatus—100%30
37ProtectNormalStatus——10
40Spike CannonNormalPhysical20100%15
54Ancient PowerRockSpecial60100%5
65Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM02HeadbuttNormalPhysical70100%15
TM03CurseGhostStatus——10
TM04RolloutRockPhysical3090%20
TM06ToxicPoisonStatus—90%10
TM08Rock SmashFightingPhysical40100%15
TM10Hidden PowerNormalSpecial60100%15
TM13SnoreNormalSpecial50100%15
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM16Icy WindIceSpecial5595%15
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM20EndureNormalStatus——10
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM34SwaggerNormalStatus—85%15
TM35Sleep TalkNormalStatus——10
TM37SandstormRockStatus——10
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
HM03SurfWaterSpecial90100%15
HM06WhirlpoolWaterSpecial3585%15

Move tutor

MoveTypeCat.PowerAcc.PP
Ice BeamIceSpecial90100%10
Gold / Silver10 level-up · 24 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
1BiteDarkPhysical60100%25
1WithdrawWaterStatus——40
1ConstrictNormalPhysical10100%35
13BiteDarkPhysical60100%25
19Water GunWaterSpecial40100%25
31LeerNormalStatus—100%30
37ProtectNormalStatus——10
40Spike CannonNormalPhysical20100%15
54Ancient PowerRockSpecial60100%5
65Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM02HeadbuttNormalPhysical70100%15
TM03CurseGhostStatus——10
TM04RolloutRockPhysical3090%20
TM06ToxicPoisonStatus—90%10
TM08Rock SmashFightingPhysical40100%15
TM10Hidden PowerNormalSpecial60100%15
TM13SnoreNormalSpecial50100%15
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM16Icy WindIceSpecial5595%15
TM17ProtectNormalStatus——10
TM18Rain DanceWaterStatus——5
TM20EndureNormalStatus——10
TM21FrustrationNormalPhysical—100%20
TM27ReturnNormalPhysical—100%20
TM32Double TeamNormalStatus——15
TM34SwaggerNormalStatus—85%15
TM35Sleep TalkNormalStatus——10
TM37SandstormRockStatus——10
TM44RestPsychicStatus——5
TM45AttractNormalStatus—100%15
TM46ThiefDarkPhysical60100%25
HM03SurfWaterSpecial90100%15
HM06WhirlpoolWaterSpecial3585%15
Yellow7 level-up · 21 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
1Horn AttackNormalPhysical65100%25
1Water GunWaterSpecial40100%25
1WithdrawWaterStatus——40
34Horn AttackNormalPhysical65100%25
39LeerNormalStatus—100%30
44Spike CannonNormalPhysical20100%15
49Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07Horn DrillNormalPhysical—30%5
TM08Body SlamNormalPhysical85100%15
TM09Take DownNormalPhysical9085%20
TM10Double-EdgeNormalPhysical120100%15
TM11Bubble BeamWaterSpecial65100%20
TM12Water GunWaterSpecial40100%25
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17SubmissionFightingPhysical8080%20
TM19Seismic TossFightingPhysical—100%20
TM20RageNormalPhysical20100%20
TM31MimicNormalStatus——10
TM32Double TeamNormalStatus——15
TM33ReflectPsychicStatus——20
TM34BideNormalPhysical——10
TM40Skull BashNormalPhysical130100%10
TM44RestPsychicStatus——5
TM50SubstituteNormalStatus——10
HM03SurfWaterSpecial90100%15
Red / Blue7 level-up · 21 TM/HM

Level-up

LvMoveTypeCat.PowerAcc.PP
1Horn AttackNormalPhysical65100%25
1Water GunWaterSpecial40100%25
1WithdrawWaterStatus——40
34Horn AttackNormalPhysical65100%25
39LeerNormalStatus—100%30
44Spike CannonNormalPhysical20100%15
49Hydro PumpWaterSpecial11080%5

TM & HM

TMMoveTypeCat.PowerAcc.PP
TM06ToxicPoisonStatus—90%10
TM07Horn DrillNormalPhysical—30%5
TM08Body SlamNormalPhysical85100%15
TM09Take DownNormalPhysical9085%20
TM10Double-EdgeNormalPhysical120100%15
TM11Bubble BeamWaterSpecial65100%20
TM12Water GunWaterSpecial40100%25
TM13Ice BeamIceSpecial90100%10
TM14BlizzardIceSpecial11070%5
TM15Hyper BeamNormalSpecial15090%5
TM17SubmissionFightingPhysical8080%20
TM19Seismic TossFightingPhysical—100%20
TM20RageNormalPhysical20100%20
TM31MimicNormalStatus——10
TM32Double TeamNormalStatus——15
TM33ReflectPsychicStatus——20
TM34BideNormalPhysical——10
TM40Skull BashNormalPhysical130100%10
TM44RestPsychicStatus——5
TM50SubstituteNormalStatus——10
HM03SurfWaterSpecial90100%15

Where to find it in the official games

Not obtainable in the wild in any of the 16 official games this site covers. In those games it has to be evolved, traded or bred — or it belongs to a game whose data is not here yet.

Where to find it in the ROM hacks

19 guides on this site put it somewhere you can catch it. Areas link to that guide's own route page, with its own rates and levels.

GuideWhere
Infinite Fusion
Tohjo FallsGood Rod (Remix) · Lv 38 · 50%
Sword and Shield Ultimate Plus
Warm Up Tunnel (Isle Of Armor)Grass · Lv 42-52 · 1%
Pokémon Phoenix Red
Mt. Moon 1FSuper Rod · Lv 30 · 20%
Route 11Super Rod · Lv 30-35 · 20%
Rock Tunnel B1FSuper Rod · Lv 26-30 · 60%
Recordkeepers
Your starting team — Sand affinityStarter pool (two drawn) · Lv 100
Radical Red
Route 18Grass (Night) · Lv 49-51 · 8%
Pokémon Emerald Kaizo
Route 115Super Rod · Lv 65 · 16%
Underwater — Route 124Surf · Lv 68 · 30%
Route 127Super Rod · Lv 65 · 15%
and 8 more areas
Pokémon Crippling Medical Debt Edition
Mauville CitySuper Rod · Lv 40-42 · 4%rare
Pokémon Platinum Kaizo
Oreburgh Gate B1FSuper Rod · Lv ? · 40%
Mt. Coronet NorthSuper Rod · Lv ? · 40%
Distortion World Area 3Day · Lv 65 · 10%
Pokémon Emerald Squared
Underwater Route 126Water · Lv 40-50 · 11.1%
Seafloor Cavern Room 1Land · Lv 40-50 · 5%
Seafloor Cavern Room 2Land · Lv 40-50 · 5%
and 10 more areas
Rising Ruby & Sinking Sapphire
Seafloor Cavern OutWalking · Lv 56
Fire Red Omega
Tanoby RuinsSurf · Lv —
Pokemon Kanto Expansion Pak
Mt. Moon CraterFishing Rod · Lv 49 · 30%
Pokémon Peridot Version
Lost LandSuper Rod · Lv 45 · 50%
Pokémon FireRed Deluxe
Crystaleye CavernSuper Rod · Lv ? · 40%
Cerulean Cave 1FSuper Rod · Lv ? · 40%
Cerulean Cave B1FSuper Rod · Lv ? · 40%
Pokémon Platinum Redux
Hidden HousePalmer · Lv ?
Mt. Coronet CavernGrass · Lv ? · 15%
Pokémon Parallel Emerald
Route 117Good Rod · Lv ? · 40%
Route 117Surf · Lv ? · 10%
Meteor Falls RestOld Rod · Lv ? · 30%
and 4 more areas
Pokémon Black Pearl Emerald
Route 124Surf · Lv 56-62 · 5%rare
Pokémon Project Nova
Paradise ParkSuper Rod · Lv 55 · 20%
Pokémon Timeless Diamond & Spaceless Pearl
Route 230Advance Radar (FireRed Cartridge) · Lv 55 · 4%
Unboundnot in the wild in this guide's tables — evolve, trade or battle it
Emerald Roguenot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Too Many Types 2not in the wild in this guide's tables — evolve, trade or battle it
Pokémon Heart & Soulnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon R.O.W.Enot in the wild in this guide's tables — evolve, trade or battle it
Celia's Stupid Romhacknot in the wild in this guide's tables — evolve, trade or battle it
Lazarusnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Odysseynot in the wild in this guide's tables — evolve, trade or battle it
Blaze Black 2 Redux & Volt White 2 Reduxnot in the wild in this guide's tables — evolve, trade or battle it
Elite Reduxnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon GS Chroniclesnot in the wild in this guide's tables — evolve, trade or battle it
Inclement Emeraldnot in the wild in this guide's tables — evolve, trade or battle it
Renegade Platinumnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Odyssey II: Heroes of Lemurianot in the wild in this guide's tables — evolve, trade or battle it
Pokémon FireRed & LeafGreen+not in the wild in this guide's tables — evolve, trade or battle it
Pokémon Aesthetic Rednot in the wild in this guide's tables — evolve, trade or battle it
Pokemon Modern Emeraldnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Valiantnot in the wild in this guide's tables — evolve, trade or battle it
Gaianot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Emerald Imperiumnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Classicnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon: Wishes of Tomorrownot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Exceedednot in the wild in this guide's tables — evolve, trade or battle it
Pokémon WaveBluenot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Hoenn's Last Wishnot in the wild in this guide's tables — evolve, trade or battle it
Low Budget Crystalnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon FireRed Reignited & LeafGreen Regrownnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Polished Crystalnot in the wild in this guide's tables — evolve, trade or battle it
Sacred Gold & Storm Silvernot in the wild in this guide's tables — evolve, trade or battle it
Blaze Black 2 & Volt White 2not in the wild in this guide's tables — evolve, trade or battle it
Pokémon SoothingSilvernot in the wild in this guide's tables — evolve, trade or battle it
Blaze Black & Volt Whitenot in the wild in this guide's tables — evolve, trade or battle it
Pokémon FireRed: Rocket Editionnot in the wild in this guide's tables — evolve, trade or battle it
HeartGold Generationsnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon CC: Operation Masqueradenot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Sour Crystalnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Spirits of the Stormnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Overcomplicatednot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Emerald Rule-ettenot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Mirror Goldnot in the wild in this guide's tables — evolve, trade or battle it
Pokémon Crystal Legacynot in the wild in this guide's tables — evolve, trade or battle it

Compare official Omastar with the ROM hacks →

In the 59 guides that include it

Changed in 30 of 59 guides: retyped in 4, stats in 14, abilities in 24, evolution in 1.

Every ROM hack on this site that has Omastar, and what it did to it. Guides that changed something are first. Click one for that version's full page — locations, moveset and TMs.

GuideTypeTotalAbilities
Pokémon Too Many Types 2ChangedRockWater→HolyAncient495—
Celia's Stupid RomhackChangedRockWater495Early Bird
+ Early Bird
Sword and Shield Ultimate PlusChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Lazarus
Evolves at Lv. 40
ChangedRockWater495
+20 Attack, -20 Sp. Atk
Skill Link, Shell Armor, Weak Armor
+ Skill Link − Swift Swim
Pokémon Phoenix RedChangedRockWater500 +5
+5 HP, -55 Defense, -10 Sp. Atk, +55 Sp. Def, +10 Speed
Swift Swim, Shell Armor
− Weak Armor
RecordkeepersChangedRockWater495Shell Armor
− Swift Swim, Weak Armor
Pokémon Emerald KaizoChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Renegade PlatinumChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Pokémon Odyssey II: Heroes of LemuriaChangedRockWater→GhostWater505 +10
+5 HP, +65 Attack, -65 Sp. Atk, +10 Sp. Def, -5 Speed
Swift Swim, Multiscale
+ Multiscale − Shell Armor, Weak Armor
Pokémon FireRed & LeafGreen+ChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Pokémon Aesthetic RedChangedRockWater505 +10
+10 Sp. Def
Weak Armor, Skill Link
+ Skill Link − Swift Swim, Shell Armor
Pokemon Modern EmeraldChangedRockWater495Swift Swim, Shell Armor
Pokémon Crippling Medical Debt EditionChanged0 -495
-70 HP, -60 Attack, -125 Defense, -115 Sp. Atk, -70 Sp. Def, -55 Speed
—
Pokémon Platinum KaizoChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Pokémon ExceededChangedRockWater→Water495Swift Swim, Weak Armor
Low Budget CrystalChangedRockWater535 +40
+15 HP, +15 Sp. Def, +10 Speed
Swift Swim
− Shell Armor, Weak Armor
Pokémon Emerald SquaredChangedRockWater495
-10 Attack, +10 Speed
Swift Swim, Shell Armor, Weak Armor
Pokémon FireRed Reignited & LeafGreen RegrownChangedRockWater535 +40
+20 Attack, +20 Sp. Def
Swift Swim, Shell Armor
− Weak Armor
Sacred Gold & Storm SilverChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Pokémon SoothingSilverChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Blaze Black & Volt WhiteChangedRockWater495Swift Swim, Iron Barbs, Weak Armor
+ Iron Barbs − Shell Armor
Fire Red OmegaChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Pokémon FireRed: Rocket EditionChangedRockWater495
-60 Sp. Atk, +45 Sp. Def, +15 Speed
Swift Swim, Shell Armor
− Weak Armor
Pokemon Kanto Expansion PakChangedRockWater540 +45
+45 Sp. Def
—
Pokémon FireRed DeluxeChangedRockWater540 +45
+5 HP, +30 Attack, +10 Speed
Shell Armor, Swift Swim
− Weak Armor
Pokémon Platinum ReduxChangedRockWater→WaterGhost552 +57
+19 HP, +7 Attack, +1 Defense, -3 Sp. Atk, +15 Sp. Def, +18 Speed
Swift Swim, Rough Skin
+ Rough Skin − Shell Armor, Weak Armor
Pokémon Project NovaChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
Pokémon Spirits of the StormChanged0 -495
-70 HP, -60 Attack, -125 Defense, -115 Sp. Atk, -70 Sp. Def, -55 Speed
Weak Armor
Pokémon Mirror GoldChangedRockWater530 +35
+25 HP, -15 Attack, -10 Defense, +5 Sp. Def, +30 Speed
Iron Barbs, Skill Link
+ Iron Barbs, Skill Link − Swift Swim, Shell Armor, Weak Armor
Pokémon Timeless Diamond & Spaceless PearlChangedRockWater495Swift Swim, Shell Armor
− Weak Armor
UnboundUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Emerald RogueUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Heart & SoulUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Infinite FusionUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon R.O.W.EUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Blaze Black 2 Redux & Volt White 2 ReduxUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Radical RedUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Elite ReduxUnchangedRockWater495Weak Armor, Swift Swim, Water Compaction
Pokémon GS ChroniclesUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Inclement EmeraldUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon ValiantUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
GaiaUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Emerald ImperiumUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon ClassicUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon: Wishes of TomorrowUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon WaveBlueUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Hoenn's Last WishUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Polished CrystalUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Blaze Black 2 & Volt White 2UnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Rising Ruby & Sinking SapphireUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Peridot VersionUnchangedRockWater495—
HeartGold GenerationsUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon CC: Operation MasqueradeUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Parallel EmeraldUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Sour CrystalUnchangedRockWater495—
Pokémon Black Pearl EmeraldUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon OvercomplicatedUnchangedRockWater495Dragons Maw, Perish Body, Primordial Sea
Pokémon Emerald Rule-etteUnchangedRockWater495Swift Swim, Shell Armor, Weak Armor
Pokémon Crystal LegacyUnchangedRockWater495—

Pokédex entries

What each game says about it, in the games' own words.

Red / BlueA prehistoric POKéMON that died out when its heavy shell made it impossible to catch prey.
YellowSharp beaks ring its mouth. Its shell was too big for it to move freely, so it became extinct.
GoldApparently, it cracked SHELLDER's shell with its sharp fangs and sucked out the insides.
Silver / SoulSilver / YOnce wrapped around its prey, it never lets go. It eats the prey by tearing at it with sharp fangs.
CrystalIts heavy shell allowed it to reach only nearby food. This could be the reason it is extinct.
Ruby / SapphireOMASTAR uses its tentacles to capture its prey. It is believed to have become extinct because its shell grew too large and heavy, causing its movements to become too slow and ponderous.
EmeraldAn OMASTAR uses its tentacles to capture its prey. It is believed to have become extinct because its shell grew too large, making its movements slow and ponderous.
FireRed / XIts tentacles are highly developed as if they are hands and feet. As soon as it ensnares prey, it bites.
LeafGreenDespite having strong fangs and tentacles, it went extinct when its heavy shell made it unable to catch prey.
Diamond / Pearl / Platinum / Black / White / Black 2 / White 2It is thought that this Pokémon became extinct because its spiral shell grew too large.
HeartGoldApparently, it cracked SHELLDER’s shell with its sharp fangs and sucked out the insides.
Omega Ruby / Alpha SapphireOmastar uses its tentacles to capture its prey. It is believed to have become extinct because its shell grew too large and heavy, causing its movements to become too slow and ponderous.
Ultra SunIts heavy shell is thought to be the reason this ancient Pokémon died out. It’s apparently a distant ancestor of Octillery.
Ultra MoonIt wraps its prey in its tentacles to immobilize them and then finishes them off with its sharp fangs.

Names in other languages

Japaneseオムスター
Japanese (Rōmaji)Omstar
GermanAmoroso
FrenchAmonistar
SpanishOmastar
ItalianOmastar
Korean암스타
Chinese (Simplified)多刺菊石兽
Chinese (Traditional)多刺菊石獸

Official data here is present-day reference data from PokéAPI, not a snapshot of any one game's era — the Fairy type and hidden abilities arrived partway through the series, so a difference against an older game can belong to the series rather than to that ROM hack.