List of permanently missable items

NOTE: This page does not include items that are missed by choosing another item (e.g. In Gen I and III, the Helix Fossil is not counted as permanently missable even though it cannot be obtained if the Dome Fossil is chosen). Items missable due to using glitches and event items are not included either.

Aqua Hideout/Magma Hideout

In Pokémon Ruby and Sapphire, the entrance to the Aqua Hideout/Magma Hideout is sealed after defeating Tate and Liza.

Item		Location	Games
	Master Ball	Middle room on 2nd floor, the top-left item a cluster of two real and two fake items, just after a maze of teleports	R  S
	Nugget	The bottom-left item in the same cluster as the Master Ball	R  S
	Max Elixir	Near generator-like thing on 2nd floor, accessible with right teleport near stairs	R  S
	Nest Ball	West-middle room on 3rd floor	R  S

Dry Lake Valor

In Pokémon Diamond, Pearl, and Platinum, Lake Valor is initially drained by a Plasma Bomb, allowing the player to walk across the lakebed. After Dialga, Palkia, or Giratina has been caught or defeated, the lake is refilled and the player can no longer access items on the lakebed.

Item		Location	Games
	HP Up	In the northwest while the lake is dry (hidden)	D  P  Pt

N's Castle

In Pokémon Black and White, the player cannot access N's Castle after defeating Ghetsis.

Item		Location	Games
	Max Potion	In the right room on the second floor	B  W
	Max Revive	In the center room on the third floor	B  W
	Ultra Ball	Gift from a Plasma Grunt in the left room on the third floor (repeatable if the player has no Poké Balls in their bag)	B  W
	Rare Candy	Inside N's room	B  W
	Full Restore	In the center room on the fourth floor	B  W