The Gas Pokemon. Found in Pokemon Tower. Gastly is frail but its Ghost/Poison typing is unique in Gen 1, and both evolutions are strong.
375HP30Attack35Defense30Speed80Sp.Def100Sp.Atk100
Gastly
Haunter
Gengar
Weak to
Physical
Attacker
80Speed · Above Avg

Is Gastly Good in Red & Blue Playthrough?

Gastly is too fragile to fight anything directly, but it's the start of the Gengar line. The Ghost typing is unique in Red and Blue. Worth catching in Pokemon Tower and evolving up.

StrongGoodEvenToughBadGTEEGEGSGSGGGBrockGym 1MistyGym 2SurgeGym 3GastlyCatchableHaunterEvolveErikaGym 4GengarEvolveKogaGym 5SabrinaGym 6BlaineGym 7GiovanniGym 8LoreleiE4BrunoE4AgathaE4LanceE4BlueChamp*
Brock
Gym 1
Good

Gastly has the type edge here and should clean up Brock's team.

You Win
Geodude
Lv 12
RockGround
Rock Head
TackleDefense Curl
Even
Onix
Lv 14
RockGround
Rock Head
TackleScreechBide
Misty
Gym 2
Tough

Misty's typing presses Gastly's defenses.

Even
Staryu
Lv 18
Water
Illuminate
TackleWater Gun
Avoid
Starmie
Lv 21
WaterPsychic
Illuminate
TackleWater GunBubble Beam
Lt. Surge
Gym 3
Even

Gastly trades roughly evenly with Lt. Surge's team.

Even
Voltorb
Lv 21
Electric
Soundproof
TackleScreechSonic Boom
Even
Pikachu
Lv 18
Electric
Static
Thunder ShockGrowlThunder WaveQuick Attack
Risky
Raichu
Lv 24
Electric
Static
Thunder ShockGrowlThunderbolt
Erika
Gym 4
Even

Haunter trades roughly evenly with Erika's team.

Even
Victreebel
Lv 29
GrassPoison
Chlorophyll
Razor LeafWrapPoison PowderSleep Powder
You Win
Tangela
Lv 24
Grass
Chlorophyll
ConstrictBind
Even
Vileplume
Lv 29
GrassPoison
Chlorophyll
Petal DancePoison PowderMega DrainSleep Powder
Koga
Gym 5
Good

Gengar has the type edge here and should clean up Koga's team.

You Win
Koffing
Lv 37
Poison
Levitate
TackleSmogSludgeSmokescreen
You Win
Muk
Lv 39
Poison
Stench
DisablePoison GasMinimizeSludge
You Win
Koffing
Lv 37
Poison
Levitate
TackleSmogSludgeSmokescreen
Even
Weezing
Lv 43
Poison
Levitate
SmogSludgeToxicSelf Destruct
Sabrina
Gym 6
Even

Gengar trades roughly evenly with Sabrina's team.

Risky
Kadabra
Lv 38
Psychic
Synchronize
DisablePsybeamRecoverPsychic
Even
Mr Mime
Lv 37
Psychic
Soundproof
ConfusionBarrierLight ScreenDouble Slap
Easy KO
Venomoth
Lv 38
BugPoison
Shield Dust
Poison PowderLeech LifeStun SporePsybeam
Risky
Alakazam
Lv 43
Psychic
Synchronize
PsybeamRecoverPsywaveReflect
Blaine
Gym 7
Good

Gengar has the type edge here and should clean up Blaine's team.

You Win
Growlithe
Lv 42
Fire
Intimidate
EmberLeerTake DownAgility
You Win
Ponyta
Lv 40
Fire
Run Away
Tail WhipStompGrowlFire Spin
You Win
Rapidash
Lv 42
Fire
Run Away
Tail WhipStompGrowlFire Spin
Even
Arcanine
Lv 47
Fire
Intimidate
RoarEmberFire BlastTake Down
Giovanni
Gym 8
Strong

Gengar resists most of Giovanni's coverage and hits back hard.

Easy KO
Rhyhorn
Lv 45
GroundRock
Lightning Rod
StompTail WhipFury AttackHorn Drill
You Win
Dugtrio
Lv 42
Ground
Sand Veil
GrowlDigSand AttackSlash
Easy KO
Nidoqueen
Lv 44
PoisonGround
Poison Point
ScratchTail WhipBody SlamPoison Sting
Easy KO
Nidoking
Lv 45
PoisonGround
Poison Point
TackleHorn AttackPoison StingThrash
Easy KO
Rhydon
Lv 50
GroundRock
Lightning Rod
StompTail WhipFissureHorn Drill
Lorelei
Elite Four
Good

Gengar has the type edge here and should clean up Lorelei's team.

Easy KO
Dewgong
Lv 54
WaterIce
Thick Fat
GrowlAurora BeamRestTake Down
Easy KO
Cloyster
Lv 53
WaterIce
Shell Armor
SupersonicClampAurora BeamSpike Cannon
You Win
Slowbro
Lv 54
WaterPsychic
Oblivious
GrowlWater GunWithdrawAmnesia
Even
Jynx
Lv 56
IcePsychic
Oblivious
Double SlapIce PunchBody SlamThrash
You Win
Lapras
Lv 56
WaterIce
Water Absorb
Body SlamConfuse RayBlizzardHydro Pump
Bruno
Elite Four
Strong

Gengar resists most of Bruno's coverage and hits back hard.

Easy KO
Onix
Lv 53
RockGround
Rock Head
Rock ThrowRageSlamHarden
Easy KO
Hitmonchan
Lv 55
Fighting
Keen Eye
Ice PunchThunder PunchMega PunchCounter
Easy KO
Hitmonlee
Lv 55
Fighting
Limber
Jump KickFocus EnergyHigh Jump KickMega Kick
Easy KO
Onix
Lv 56
RockGround
Rock Head
Rock ThrowRageSlamHarden
Easy KO
Machamp
Lv 58
Fighting
Guts
LeerFocus EnergyFissureSubmission
Agatha
Elite Four
Good

Gengar has the type edge here and should clean up Agatha's team.

You Win
Gengar
Lv 56
GhostPoison
Cursed Body
Confuse RayNight ShadeHypnosisDream Eater
Easy KO
Golbat
Lv 56
PoisonFlying
Inner Focus
SupersonicConfuse RayWing AttackHaze
Easy KO
Haunter
Lv 55
GhostPoison
Levitate
Confuse RayNight ShadeHypnosisDream Eater
Easy KO
Arbok
Lv 58
Poison
Intimidate
BiteGlareScreechAcid
You Win
Gengar
Lv 60
GhostPoison
Cursed Body
Confuse RayNight ShadeToxicDream Eater
Lance
Elite Four
Good

Gengar has the type edge here and should clean up Lance's team.

Easy KO
Gyarados
Lv 58
WaterFlying
Intimidate
Dragon RageLeerHydro PumpHyper Beam
You Win
Dragonair
Lv 56
Dragon
Shed Skin
AgilitySlamDragon RageHyper Beam
You Win
Dragonair
Lv 56
Dragon
Shed Skin
AgilitySlamDragon RageHyper Beam
Easy KO
Aerodactyl
Lv 60
RockFlying
Rock Head
SupersonicBiteTake DownHyper Beam
Even
Dragonite
Lv 62
DragonFlying
Inner Focus
AgilitySlamBarrierHyper Beam
Blue
Champion
Good

Gengar has the type edge here and should clean up Blue's team.

Even
Pidgeot
Lv 61
NormalFlying
Keen Eye
WhirlwindWing AttackSky AttackMirror Move
Risky
Alakazam
Lv 59
Psychic
Synchronize
PsybeamRecoverPsychicReflect
Easy KO
Rhydon
Lv 61
GroundRock
Lightning Rod
Tail WhipFury AttackHorn DrillLeer
You Win
Arcanine
Lv 61
Fire
Intimidate
RoarEmberLeerTake Down
Even
Exeggutor
Lv 63
GrassPsychic
Chlorophyll
BarrageHypnosisStomp
Easy KO
Blastoise
Lv 65
Water
Torrent
BiteWithdrawBlizzardHydro Pump

Catchable

Available after Badge 3
Type
GhostPoison
Tier
E

Catch Gastly in Pokémon Tower (walking, Lv 18-24, common). Needs the Silph Scope; without it every Pokemon here is an unidentified Ghost that cannot be caught.

View Gastly locations

Evolve Gastly to Haunter

Level 25
Type
GhostPoison
Tier
A

Gastly evolves into Haunter at Level 25. Your Gastly should hit Level 25 before you reach Erika, at typical leveling pace.

View Haunter locations

Recommended Moves

  • STARTING (Lv 25)
    • LV 25GhostNight ShadePower 50Accuracy 100%PP 15
  • After Lt. Surge
    • LV 29PsychicHypnosisPower —Accuracy 60%PP 20
    • LV 38PsychicDream EaterPower 100Accuracy 100%PP 15
  • After Koga
  • After Giovanni

Evolve Haunter to Gengar

Trade
Type
GhostPoison
Tier
S

Haunter evolves into Gengar when traded. Most players are ready to trade before reaching Koga.

Recommended Moves

How to Get Gastly in Red & Blue

The Pokemon Tower in Lavender is the lone home for Gastly, ten common encounters across its haunted floors. This is the only Ghost-type line in the game, so the Tower is mandatory.

1 location to catch Gastly

Encountered via tall grass encounters

Badge 4

Where To Catch Gastly in RB

Gastly is where the line starts, caught through walking encounters at Lv. 18-24. The chain covers 2 catchable stages before reaching the final form.

  1. Gengar
    Step 3Evolve into Gengar

Not landing the catch? Calculate Gastly catch rates for Red & Blue by ball, status, and HP.

Gastly Weakness

Gastly is weak to Ground, Psychic, and Ghost. On the flip side, it's immune to Normal and Fighting-type moves entirely. Gastly's special bulk (base 100 Special) helps absorb special-type weaknesses, though physical moves exploit the lower Defense.

Gastly Weakness and Resistance Chart
DamageTypes
2x (Weak)Ground, Psychic, Ghost
0.5x (Resist)Grass
0.25x (Resist)Poison
0x (Immune)Normal, Fighting
Gen I Type Chart
  • Only 15 types exist — Dark, Steel, and Fairy are absent
  • Ghost has no effect on Psychic (a known bug, fixed in Gen II)
  • Special stat governs both offense and defense — no Sp.Atk / Sp.Def split

What is Gastly Weak Against

Good
3Weak
2Resist
2Immune
Score+3
4xCritical
None
½xResist
¼xResist

What is Gastly Strong Against

3Strong
0Resisted
0Immune
Score+3
½xResisted
None
0xImmune
None

Best Pokemon Against Gastly

Hypno
Hypno
Psychic
C
Kadabra
Kadabra
Psychic
B
Haunter
Haunter
GhostPoison
C

Gastly Evolutions

Gastly evolves into Gengar, but can't breed. At 375 stats as a Ghost/Poison type, evolution is the only path. Evolving adds up to 125 stat points total. View every chain in the Evolution Chart.

How to Evolve

3 Forms
Stat Comparison 3 Stages
Gastly
GhostPoison
Haunter
GhostPoison
Gengar
GhostPoison
HP
30
45+15
60+15
ATK
35
50+15
65+15
DEF
30
45+15
60+15
SP.ATK
100
115+15
130+15
SP.DEF
35
55+20
75+20
SPE
80
95+15
110+15
BST
310E-Tier
405A-Tier+95
500S-Tier+95
ROLE
Attacker
Cannon
Sweeper
TYPE
Special
Special
Special
Breeding not available · Introduced in Gen 2

RB Gastly Best Moveset

100 Special and 80 Speed on a Ghost/Poison frame, surprisingly competitive for a pre-evolution. MoveHypnosis puts threats to sleep, and Normal immunity blocks MoveBody Slam and MoveHyper Beam. Genuinely usable without needing to evolve into Gengar.

Best Build

Experimental
Support
Ability
Unknown
Item
None
Best Nature for Gastly
HardyNEUTRAL

Support Moveset

  • ExplosionCoverage
  • HypnosisUtility
  • SubstituteUtility
  • ThunderboltCoverage

Moves List

Most of Gastly's flexibility comes from TMs. Same-type output runs through Lick and Night Shade, but Psychic and Normal and the rest of the TM pool push it from predictable to genuinely threatening.

Level-Up Moves

Lv 1
Confuse Ray
A—10010Ghost
Lv 1
Lick
—3010030Ghost
Lv 1
Night Shade
D—10015Ghost
Lv 27
Hypnosis
B—6020Psychic
Lv 35
Dream Eater
—10010015Psychic

TM Moves

All 15 TMs are obtainable before the Elite Four

TM
TM34D——10Normal
TM32
Double TeamSafari Zonebadge 3
———15Normal
TM42
Dream EaterViridian Citybadge 2
—10010015Psychic
TM47
ExplosionVictory Road 3Fnot until badge 8
B2501005Normal
TM21D4010010Grass
TM31
MimicSaffron Citybadge 5
D——10Normal
TM29
PsychicSaffron Citybadge 5
B9010010Psychic
TM46——10015Psychic
TM20
RageRoute 15badge 3
D2010020Normal
TM44
RestS.S. Annebadge 2
C——10Psychic
TM36
Self-DestructSilph Co.badge 5
C2001005Normal
TM50
SubstituteRocket Game Cornerbadge 3
B——10Normal
TM25
ThunderKanto Power Plantbadge 5
C1107010Electric
TM24B9510015Electric
TM06C—9010Poison

Tutor Moves

Gastly can't learn any Tutor moves

Base Stats

Base Stats
Avg
HP30
F
Attack35
F
Defense30
F
Sp. Atk100
B
Sp. Def100
B
Speed80
C
Total375
Details
Catch Rate
Easy190 / 255
Growth Rate
Medium Slow1.06M XP
Height1.3 m
Weight0.1 kg
Base XP62
EV Yield
HPAtkDefSpA+1SpDSpe
Special Attack training source
Pokedex Entry

Almost invisible, this gaseous POKéMON cloaks the target and puts it to sleep without notice.

Pokemon Red / Pokemon Blue

Gastly Red & Blue Guide

  • In Red & Blue, for a casual playthrough, Gastly works as a placeholder. Ghost/Poison coverage is useful early. The real payoff is Haunter. That's where the stats start mattering.

  • In Red & Blue, Gastly plays as a attacker. Speed is middling, so pick your spots carefully.

Game Availability

Present since Red & Blue, Gastly appears in 22 games spanning 9 generations. Gen 1 originals like Gastly have the longest track record of availability in the series.

Explore

Was this page helpful?
Thanks for your feedback!
Want to tell us more?
What was most useful?
What could be improved?
Thanks for your feedback