Pokémon with Drizzle summon rain as they enter the battle. The effects are the same as Rain Dance though until the sixth generation, it lasted indefinitely. Now, it lasts 5 turns and can be extended to 8 turns with a Damp Rock. If there is another Pokémon with a weather ability, the slower one overrides the faster Pokémon's ability. If heavy rain, extremely harsh sunlight, or a mysterious air current is present, Drizzle will fail to activate.
Pokémon with Ability
As a Hidden Ability