Mixed
Balanced
340Low
35Very Slow
DTier

Mid-stage Pokemon like Koffing rarely see competitive play outside of special formats. It's a waypoint on the road to Weezing, which is where the real potential kicks in. Known as the Poison Gas Pokemon. Can go either physical or special depending on the set.

Defense and Attack carry most of Koffing's stat budget. Speed's the obvious dump stat. Common in the wild and yields 1 Defense EV. Follows a medium-fast 1M XP curve.

Base Stats
340Avg
HP40
D
Attack65
C
Defense95
B
Sp. Atk60
C
Sp. Def45
D
Speed35
F
Total340
Low <60
Avg 60-89
High 90-149
Top 150+
EV YieldDefeating Koffing yields +1 Def
HPAtkDef+1SpASpDSpe
Details
Catch190Easy•Medium Fast1M XP•0.6m / 2'00"•1kg / 2.2 lbs•68Base XP
Pokedex Entries

In hot places, its internal gases could expand and explode without any warning. Be very careful!

Yellow

Koffing Weakness

Vulnerable

Ground, Psychic, and Bug-type moves hit Koffing for super-effective damage. Koffing's physical bulk (base 95 Def) helps cushion physical weakness hits, but special attackers are the bigger threat.

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
4xCriticali
None
2xWeaki
GroundPsychicBug
½xResisti
GrassFightingPoison
¼xResisti
None
0xImmunei
None
STAB (2)i
GrassBug
3Weak
3Resist
0Immune
Scorei-3
Abilities
LevitateEvades ground moves.
Neutralizing GasNeutralizes abilities of all Pokémon in battle.
StenchHAHas a 10% chance of making target Pokémon flinch with each hit.
Levitate grants Ground immunity

You'll evolve Koffing into Weezing the traditional way. This Poison type doesn't breed despite having a chain ahead. The evolved forms gain up to 150 total stats over Koffing.

How to Evolve

2 Forms
Koffing
#109Koffing
35
Level 35
Weezing
#110Weezing
Stat Comparison 2 Stages
Koffing
Poison
Weezing
Poison
HP
40
65+25
ATK
65
90+25
DEF
95
120+25
SP.ATK
60
85+25
SP.DEF
45
70+25
SPE
35
60+25
BST
340C-Tier
490B-Tier+150
ROLE
Balanced
Balanced
TYPE
Utility
Mixed
Breeding not available · Introduced in Gen 2

Start with flexible EVs EVs. A nature nature gives Koffing the right balanced lean, an item adds extra utility, and an ability works in the background. Sludge is the main damage option.

Best Build

Utility
Ability
Not in Gen 1
Item
Not in Gen 1
Nature
Not in Gen 1

Best Koffing Moveset

  • ExplosionCoverage
  • Fire Blast
  • SludgeSTAB
  • ThunderCoverage

Recommended Teammates

Charizard
CharizardExcellent
Persian
PersianExcellent
Electabuzz
ElectabuzzExcellent

Level-up moves are just the starting point for Koffing. TMs unlock Normal and Fire coverage and turn a straightforward STAB kit around Sludge and Smog into something with actual range.

Level-Up Moves

Lv 1
Smog
207020Poison
Lv 1
Tackle
3510035Normal
Lv 32
Sludge
6510020Poison
Lv 37
Smokescreen
—10020Normal
Lv 40
Self-Destruct
2001005Normal
Lv 45
Haze
——30Ice
Lv 48
Explosion
2501005Normal

TM Moves

Src
TM34
Bide+1
——10Normal
TM32
Double Team
——15Normal
TM47
Explosion
2501005Normal
TM38
Fire Blast
120855Fire
TM31
Mimic
——10Normal
TM20
Rage
2010020Normal
TM44
Rest
——10Psychic
TM36
Self-Destruct
2001005Normal
TM50
Substitute
——10Normal
TM25
Thunder
1107010Electric
TM24
Thunderbolt
9510015Electric
TM06
Toxic
—9010Poison

Egg Moves

Koffing doesn't have any Egg moves

Tutor Moves

Koffing can't learn any Tutor moves

No wild encounters for Koffing in Yellow. It's available in Red, Gold, or Sword and can be transferred over. The details below show where to find it.

Koffing is not available as a wild encounter in this game.

Catch in the wild in:

RedWalking · Pokémon Mansion

Then trade to Yellow.

Also found in:

GoldCrystalRubyEmeraldFireRedPlatinum

  • Koffing is meant to evolve into Weezing. At 340 BST, the stats aren't there for competitive play yet. Pre-evolution Pokemon rarely hold up against fully evolved threats.

  • Watch for Rhydon (Ground), Alakazam (Psychic), and Pinsir (Bug) when using Koffing. They all hit it super-effectively with STAB. At base 35 Speed, Koffing won't outrun any of these threats so switching to a resist is usually the safer play.

  • Koffing can evolve into Weezing and Galarian Weezing depending on the method. Koffing is the base form in a 3-stage evolutionary line.

  • Base 35 Speed is low. Priority moves or Trick Room are the way to go. On offense, Koffing is a mixed attacker — base 65 Attack and 60 Sp. Atk.

  • Koffing appears in 20 games, including Yellow, Red & Blue, and Gold & Silver.

One of the original 151, Koffing 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.