Smog

Smog (スモッグ, Smog) is a damage-dealing Poison-type move introduced in the first generation.

Gen I to V
Smog inflicts damage and has a 40% chance of poisoning the target. Smog can also be used as part of a Pokémon Contest combination, causing Smoke Screen to give extra three appeal points if used in the next turn.

Gen VI Onwards
Smog's power changed from 20 to 30.