X Sp. Def is an item in the “Stat boosts” category (Battle Items). It costs ₽2000.
In-game descriptions
| Diamond / Pearl · Platinum · HeartGold / SoulSilver · Black / White · Black 2 / White 2 | An item that raises the Sp. Def stat of a Pokémon in battle. It wears off if the Pokémon is withdrawn. |
|---|---|
| X / Y | An item that boosts the Sp. Def stat of a Pokémon during a battle. It wears off once the Pokémon is withdrawn. |
| Sun / Moon · Ultra Sun / Ultra Moon · Let’s Go, Pikachu! / Let’s Go, Eevee! · Sword / Shield | An item that sharply boosts the Sp. Def stat of a Pokémon during a battle. It wears off once the Pokémon is withdrawn. |
Where to find it
Not placed on the atlas maps (so far: Red/Blue and Generation 3).
Sources : PokeAPI (items, item_flavor_text, machines) · atlas · pokeemerald species_info.h