Drizzle is an Ability. One Pokémon can have this ability, exclusively as a hidden ability.
Drizzle summons rain in battle as soon as a Pokémon with Drizzle enters the battle. Its effects are the same as the move Rain Dance, but instead of lasting for finite turns will continue for the whole battle (unless it is replaced by another weather condition). If a Pokémon with Drizzle is sent out at the same time as another Pokémon whose Ability affects the weather, the slower Pokémon's Ability will override the faster Pokémon's Ability.
Pokémon with Drizzle
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