Rarity

Rarity or availability describes how frequently a Pokémon appears in the wild, or how easily it can be caught and added to the Pokédex through other means.

The rarity of a Pokémon may vary between different games or regions, or even between locations in the same region.

Rarity levels

Common

Common Pokémon are the most plentiful and easy to come by. Not only are they abundant, but they usually have a high catch rate as well. Most of the Pokémon in this group are basic, unevolved Pokémon.

In the Trading Card Game and Trading Figure Game, common Pokémon are marked with .

Uncommon

Uncommon Pokémon are not as easily found as common Pokémon, and may take some effort to locate and capture. Both evolved and unevolved Pokémon are often found in this group.

In the Trading Card Game and Trading Figure Game, uncommon Pokémon are marked with .

Rare

Rare Pokémon are the most difficult to locate and capture in the wild. Some rare Pokémon cannot be captured in the wild, and must be evolved or obtained through other means. Evolved and legendary Pokémon frequently fall into this group.

In the Trading Card Game and Trading Figure Game, rare Pokémon are marked with .

One-time Pokémon

These are Pokémon that only appear once per Pokémon game, if at all. Legendary Pokémon are most common in this tier, though there are several others, such as Hitmonchan, who are only available once without breeding. Often, in the TCG, they are holofoil cards, though being a holofoil card does not automatically guarantee that a Pokémon is a one-time Pokémon.

Swarm

Main article: Mass Outbreak

Pokémon that only appear in a swarm. In Generation II, many Pokémon swarmed, and players were alerted to this by a call from a trainer on their Pokégear. In Generation III, it was announced on the many televisions. In Generation IV, it is announced by Dawn/Lucas's sister in Sandgem Town, who hears about it on television.In HeartGold and SoulSilver it is announced on Mary & Oak's radio station on the Pokégear.