List of permanently missable Pokémon

This is a list of permanently missable Pokémon in the games.
These are Pokémon species that the player may potentially obtain in the games, but may become permanently unavailable depending on the circumstances. Even if the player is unable to catch a certain Pokémon in the current game, they may still obtain other Pokémon of the same species by trading or transferring with other players.
==Gift Pokémon==
Most of the gift Pokémon are obtainable only once per game. Some of these Pokémon (as well as their evolutions and previous evolutionary stages, if any) are not available anywhere else in the game, except by trades or transfers from other games, or by the gift Pokémon once it is obtained. Therefore, if the player loses any of these scarce gift Pokémon by either releasing it or trading it away without breeding it first, then it and its evolutionary line will not be available anywhere else in the current game.
For instance, in several Pokémon games, the only way to obtain a first partner Pokémon of the current region (outside of trades and transfers from other games) is by choosing that first partner Pokémon at the beginning of the game. In some games, it is also possible to obtain one or more first partner Pokémon from other regions as gifts. If the player releases it or trades it away without breeding it first, then that first partner Pokémon and its evolutions would be unavailable in the current game.
As another example, in , the player is able to choose between receiving a or a . The player may then breed it to obtain , which can evolve into either of these Pokémon, as well as into . If the player obtains Hitmonlee or Hitmonchan but then releases it or trades it away without breeding it, then the whole evolutionary line (Tyrogue, Hitmonlee, Hitmonchan, and Hitmontop) would be unavailable in the current game.
===Bulbasaur (Yellow)===
In , the player may be permanently unable to receive the single available . If this Bulbasaur becomes unavailable, its evolutions and would not be obtainable either.
To receive this Bulbasaur, the player's received at the start of the game needs to have a friendship value of at least 147. The Pikachu does not need to still be in that copy of Pokémon Yellow in order to receive the Bulbasaur, as long as its friendship value was at least 147.
If the partner Pikachu is , traded away and evolved, or sent to Pokémon Bank (from the Virtual Console version), it is no longer possible to return it Pokémon Yellow to raise its friendship. If this is done before its friendship is raised to 147 or higher, it becomes impossible to receive this Bulbasaur.
A Pikachu is recognized as the partner Pikachu if it has the same Original Trainer name and Trainer ID number as the Pokémon Yellow player. It is theoretically possible for another Generation I or II game to have a Pikachu with these properties, but in practice this is very unlikely without RNG manipulation or glitches.
	
	
	
	
==Wild Pokémon from in-game events==
There are several wild Pokémon battles from in-game events. They include some Legendary Pokémon and other Pokémon visible in the overworld, as well as roaming Pokémon.
In most core series games, there is only one per species of Legendary Pokémon. In some cases, there is also a limited supply of other wild Pokémon from in-game events. For instance, there are only two in Pokémon Red, Blue, Yellow, FireRed, and LeafGreen, and only one in (this Sudowoodo respawns in ). Additionally, the player can breed several of these Pokémon to obtain more Pokémon of the same species. However, it is not possible to breed any Legendary Pokémon.
* In any game prior to , if the player defeats any of these Pokémon, they will not appear again unless they are time-based appearances (such as a that appears every Friday on and their remakes, or a that also appears every Friday, in and their remakes) or their event triggers can be repeated (such as in Diamond, Pearl and Platinum).
* In Generation I, Generation II, and , if the player runs from any of these Pokémon, it becomes permanently unavailable.
* Additionally, even after the player obtains any of these Pokémon, the player may still lose it by either releasing it or trading it away.
===Fake items===
There are , , , and disguised as items in some games. They do not respawn if they are defeated. In most cases, other Pokémon of the same species are found elsewhere in the same games. However, in , the only Electrode available are the ones disguised as items in Team Rocket's Castle, so if they are defeated or skipped (as the area cannot be revisited after defeating Giovanni), Electrode cannot be caught in these games. This is also the only way to get an Electrode in a Beast Ball in these games. Additionally, the only way to obtain Voltorb is to breed said Electrode with .
	
===Ho-Oh (Pokémon Crystal)===
In , the player must catch the three Legendary beasts and enter the Hall of Fame in order to obtain the Rainbow Wing, which is required before can appear. If the player defeats (or catches and then transfers to Pokémon Bank or releases) any of the Legendary beasts before obtaining the Rainbow Wing, then Ho-Oh will be permanently unavailable. Defeating the Legendary Beast will also lock the player out of obtaining its Pokédex entry.
The game checks for Legendary beasts in the player's party and Pokémon Storage System. , , and are recognized as the player's OT if they have the same Original Trainer name and Trainer ID number as the Pokémon Crystal player. It is theoretically possible for another Generation II game to have the Legendary beasts with these properties, but in practice this is very unlikely without RNG manipulation or glitches.
Due to an an oversight, only the first five letters of the OT name are verified. For example, if the player's name is “CRYSTAL”, then having the Legendary beasts with the OT name “CRYST” and a matching ID of the player will enable the event. This is due to the player names in the original Japanese version being a maximum of five characters long and the English version failing to account for the change.
	
	
===Roaming Roar bug (Pokémon FireRed and LeafGreen)===
Due to in , if the wild or uses , that Pokémon becomes permanently unavailable in the current game. ( is unaffected by this glitch, because it does not have Roar in its moveset when found in these games.)
			
			
==Shadow Pokémon==
Due to in Pokémon XD: Gale of Darkness, if the player loses the battle with Miror B. at the Cave Poké Spot, his Shadow will not reappear in any of the rematches against Miror B. This locks the player out of capturing the Voltorb, and in turn the Shadow without completely restarting the game.
			
			
==Mutually exclusive Pokémon==
In some cases, there are multiple Pokémon potentially available in a single game, but the player must choose one of them or otherwise can't catch all of them in a single game. They include many trios of first partner Pokémon, some Fossil Pokémon, and in some cases Legendary Pokémon.
For instance, the player is able to choose between , , and as their first partner Pokémon in Pokémon Red, Blue, FireRed, and LeafGreen. The player may also choose one of these Pokémon as a gift given by Professor Oak in , by Professor Sycamore in , and by Grand Oak in Pokémon HOME.
==Item scarcity==
In some games, there is a limited supply of certain Evolution stones or Incenses. If the player loses some of these items, then the respective Pokémon evolutions or pre-Evolutions may be unavailable outside of trades.
The player may lose these items by selling or discarding them, or a Pokémon holding them may be traded away or . Some moves (such as and ) may also cause a Pokémon to lose its held item. Additionally, the Evolution stones are consumed when used to evolve a Pokémon; once all Evolution stones of a certain kind are used up, the player will be unable to evolve the respective Pokémon in the current game. 
Some examples:
* There are five Moon Stones available in , which are more than enough to evolve all the four compatible Pokémon in these games (, , , and into , , , and , respectively). However, if the player evolves some repeated Pokémon of the same species (for instance by evolving five Jigglypuff into Wigglytuff), then the other evolutions would become unavailable in the current game.
* In , multiple Pokémon can evolve with a Fire Stone, Water Stone, Thunderstone, or Leaf Stone, but each of these stones is available only once per game (except for trades or Mystery Gift), so the player is unable to in a single game.
* In , there is only one Sea Incense available. The only way to obtain outside of trades is by breeding or holding that item. Therefore, if the player loses that item, it would not be possible to obtain Azurill in the current game.
==Event Pokémon==
Some Pokémon, including Mythical Pokémon, have been distributed in real-life events, as well as via Wi-Fi, Nintendo Network, or serial codes. Sometimes, the Pokémon were distributed directly, but at other times an item was distributed leading to the respective Pokémon. However, these Pokémon and items have become unavailable once their respective events ended. Additionally, the real-life events were restricted to some regions, so they were not available anywhere else in the first place.
Usually, these Pokémon and items have been distributed only for some of the latest games, although some of the older Mythical Pokémon (such as ) have been repeatedly distributed in new events for each generation. When someone starts a new game on an older system such as the Game Boy or Game Boy Advance, they may not have access to any of the Pokémon from past events (except via trades, cheating, or in some cases glitches).
Certain Wonder Cards can be shared with other players, meaning that theoretically these event Pokémon can be obtained at any point after their distribution has ended, if a save file with the Wonder Card is found.
==Related articles==
* List of permanently missable items
Category:Lists of Pokémon
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