Effect Spore is an ability that makes the foe poisoned, paralyzed, or fall asleep 30% of the time whenever attacked by a move that makes contact.
The chance of inflicting a given status is not the same for each status. Overall, Effect Spore has a 9% chance of inducing poison, 10% chance of inducing paralysis, and 11% chance of inducing sleep. It was introduced in Generation III. It is an exclusive ability to Grass-type Pokémon.