| Harden | Details | Level Up | TM | Move Tutor | Egg Move |
| Gen IX Dex | Gen VIII Dex | Gen VII Dex | Gen VI Dex | Gen V Dex |
| Gen IV Dex | Gen III Dex | Gen II Dex | Gen I Dex |
| Attack Name | Battle Type | Contest Type |
| Harden |  |  |
| Power Points | Base Power | Accuracy |
| 30 | 0 | 0 |
| Battle Effect: Stiffens the body's muscles to raise DEFENSE. |
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| Secondary Effect: Raises user's DEFENSE one stage. | Effect Rate: -- % |
|
| TM # | Appeal Points | Jam Points |
| None | 
| |
| Contest Effect: Can avoid being startled by others once. |
||
| BrightPowder | King's Rock | Physical Contact |
| No | No | No |
| Battle Palace Style | Battle Arena | Pokémon Hit in Battle |
| Defense | +0 | User |
| Picture Example of Harden | ||
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Pokémon That Learn Harden By Level Up in Ruby/Sapphire/Emerald/Colosseum/XD:
| No. | Pic | Name | Type 1 | Type 2 |
| #011 |  | Metapod |  |  |
| #011 | | Metapod | | |
| #014 |  | Kakuna | |  |
| #014 | | Kakuna | | |
| #088 |  | Grimer | | |
| #089 |  | Muk | | |
| #089 | | Muk | | |
| #095 |  | Onix |  |  |
| #098 |  | Krabby |  | |
| #099 |  | Kingler | | |
| #120 |  | Staryu | | |
| #127 |  | Pinsir | | |
| #140 |  | Kabuto | | |
| #141 |  | Kabutops | | |
| #207 |  | Gligar | |  |
| #208 |  | Steelix |  | |
| #211 |  | Qwilfish | | |
| #218 |  | Slugma |  | |
| #219 |  | Magcargo | | |
| #222 |  | Corsola | | |
| #266 |  | Silcoon | | |
| #266 | | Silcoon | | |
| #268 |  | Cascoon | | |
| #268 | | Cascoon | | |
| #273 |  | Seedot |  | |
| #274 |  | Nuzleaf | |  |
| #275 |  | Shiftry | | |
| #290 |  | Nincada | | |
| #291 |  | Ninjask | | |
| #292 |  | Shedinja | |  |
| #299 |  | Nosepass | | |
| #304 |  | Aron | | |
| #305 |  | Lairon | | |
| #305 | | Lairon | | |
| #306 |  | Aggron | | |
| #306 | | Aggron | | |
| #337 |  | Lunatone | |  |
| #338 |  | Solrock | | |
| #341 |  | Corphish | | |
| #342 |  | Crawdaunt | | |
| #342 | | Crawdaunt | | |
| #343 |  | Baltoy | | |
| #344 |  | Claydol | | |
| #344 | | Claydol | | |
| #347 |  | Anorith | | |
| #348 |  | Armaldo | | |
| #348 | | Armaldo | | |
| #369 |  | Relicanth | | |
Pokémon That Learn Harden By Level Up in Fire Red/Leaf Green:
| No. | Pic | Name | Type 1 | Type 2 |
| #011 | | Metapod | | |
| #011 | | Metapod | | |
| #014 | | Kakuna | | |
| #014 | | Kakuna | | |
| #088 | | Grimer | | |
| #089 | | Muk | | |
| #089 | | Muk | | |
| #095 | | Onix | | |
| #098 | | Krabby | | |
| #099 | | Kingler | | |
| #099 | | Kingler | | |
| #120 | | Staryu | | |
| #127 | | Pinsir | | |
| #140 | | Kabuto | | |
| #141 | | Kabutops | | |
| #207 | | Gligar | | |
| #208 | | Steelix | | |
| #211 | | Qwilfish | | |
| #218 | | Slugma | | |
| #219 | | Magcargo | | |
| #222 | | Corsola | | |
| #266 | | Silcoon | | |
| #266 | | Silcoon | | |
| #268 | | Cascoon | | |
| #268 | | Cascoon | | |
| #273 | | Seedot | | |
| #274 | | Nuzleaf | | |
| #275 | | Shiftry | | |
| #290 | | Nincada | | |
| #291 | | Ninjask | | |
| #292 | | Shedinja | | |
| #299 | | Nosepass | | |
| #304 | | Aron | | |
| #305 | | Lairon | | |
| #305 | | Lairon | | |
| #306 | | Aggron | | |
| #306 | | Aggron | | |
| #337 | | Lunatone | | |
| #338 | | Solrock | | |
| #341 | | Corphish | | |
| #342 | | Crawdaunt | | |
| #342 | | Crawdaunt | | |
| #343 | | Baltoy | | |
| #344 | | Claydol | | |
| #344 | | Claydol | | |
| #347 | | Anorith | | |
| #348 | | Armaldo | | |
| #348 | | Armaldo | | |
| #369 | | Relicanth | | |
Pokémon That Learn Harden By Breeding:
| No. | Pic | Name | Type 1 | Type 2 |
| #214 |  | Heracross | |  |
Pokémon That Learn Harden By Purifying or A Special Way:
| No. | Pic | Name | Type 1 | Type 2 |