Unburden is an ability introduced in Generation IV.
Effect
This ability doubles the Speed if the Pokémon's held item is used up or loses such item. This ability doesn't works if the Pokémon doesn't have an item at the beginning of the battle, and if it happens to have one the Pokémon will switch it with the moves Trick or Switcheroo with the rival.
Description
| Generations | Description |
|---|---|
| Generation IV | Boosts the Speed stat if the Pokémon's held item is used or lost. |
| Generation V | |
| Generation VI | |
| Generation VII | |
| Generation VIII | |
| Generation IX |
Pokémon
| Pokémon | Type | First Ability | Second Ability | Hidden Ability | |
|---|---|---|---|---|---|
 | Drifloon |  Ghost /  Flying | Aftermath | Unburden | Flare Boost |
 | Drifblim | Ghost / Flying | Aftermath | Unburden | Flare Boost |
 | Purrloin |  Dark | Limber | Unburden | Prankster |
 | Liepard | Dark | Limber | Unburden | Prankster |
 | Hawlucha |  Fighting / Flying | Limber | Unburden | Mold Breaker |
 | Nickit | Dark | Run Away | Unburden | Stakeout |
 | Thievul | Dark | Run Away | Unburden | Stakeout |
 | Sneasler | Fighting /  Poison | Pressure | Unburden | Poison Touch |
 | Shroodle | Poison /  Normal | Unburden | Pickpocket | Prankster |
 | Grafaiai | Poison / Normal | Unburden | Poison Touch | Prankster |
 | Hitmonlee | Fighting | Limber | Reckless | Unburden |
 | Treecko |  Grass | Overgrow | — | Unburden |
 | Grovyle | Grass | Overgrow | — | Unburden |
 | Sceptile | Grass | Overgrow | — | Unburden |
 | Accelgor |  Bug | Hydration | Sticky Hold | Unburden |
 | Swirlix |  Fairy | Sweet Veil | — | Unburden |
 | Slurpuff | Fairy | Sweet Veil | — | Unburden |