Abilities

Abilities are passive effects that each Pokémon possesses for use in battle. A Pokémon may only have one Ability at a time; this Ability cannot be changed. A Pokémon's Ability is decided when the Pokémon spawns, and is chosen from a pool of up to three possible Abilities that the Pokémon can have, depending on the Pokémon's species.

Of the pool of possible Abilities a Pokémon can have, there are one or two normal Abilities and possibly one hidden Ability. If the Pokémon has two possible normal Abilities, there is an equal chance that either of them will be that Pokémon's Ability. Hidden Abilities are significantly rarer than normal Abilities; by default, a wild Pokémon has a 1/150 chance of having its hidden Ability. The combination of types of Abilities that a Pokémon may have include:

One normal Ability
One normal Ability, one hidden Ability
Two normal Abilities, one hidden Ability

Abilities, including hidden Abilities, can be passed down through breeding. There is an 80% chance that the mother Pokémon will pass down her Ability; the other 20% of the time, the Ability is chosen randomly from the Pokémon's normal Abilities (with no chance of a hidden Ability). Along similar lines, the father has a 60% chance of passing down his Ability if he breeds with a Ditto.

A Pokémon may change between its two normal Abilities using an Ability Capsule. However, an Ability Capsule cannot change a Pokémon's normal Ability into its hidden Ability or vice versa. In Creative mode, it is possible to toggle a Pokémon's Ability (including to and from its hidden Ability) using a Pokémon editor.

List of Abilities

Config settings

"hiddenAbilitySpawnRate": The chance of wild or spawned-in Pokémon having their hidden Abilities. This setting does not affect breeding.

NBT tag storage

While Abilities themselves are stored in data as NBT tags, there is also a separate tag known as the "Ability slot", which is also created upon the spawning of the Pokémon. This value is where the Pokémon's Ability derives from and controls what the Pokémon's Ability will change to upon evolution (if applicable). It is also used when determining the chances of getting each possible Ability when breeding.

Through the use of external NBT editors, it is possible to change a Pokémon's Ability. However, if the Pokémon's Ability slot is not also modified correctly, side effects will occur. For example, if a Pokémon spawns in with a normal Ability and is edited to have its hidden Ability without changing the Ability slot, it will be impossible for the Pokémon to pass down its Ability through breeding as the breeding algorithm relies on the Ability slot, which is still routed to a normal Ability in this case.