Koffing is a spherical Pokémon filled with toxic gases. It has vacant eyes and a wide mouth that typically features two pointed teeth in the upper jaw, though a full set of teeth has been shown in the anime. Below its face is a cream-colored skull-and-crossbones marking. Several geyser-like protrusions, which usually emit a mustard-colored gas, cover this Pokémon's body. Koffing's purple skin is extremely thin, and over-inflation can cause it to explode. The Pocket Monsters Carddass Trading Cards depict Koffing as having a hollow body.
Koffing generates gases within its body by combining toxins with garbage, producing more gas in higher temperatures. These gases are foul-smelling and cause sniffles, coughs, and teary eyes to those nearby. The gases are lighter than air, enabling Koffing to hover. When agitated, it produces a more toxic gas and expels it through the holes in its body. As demonstrated in the anime, Koffing's gas can be ignited by fire or electricity. It feeds on the fumes from raw, rotting trash found in gas dumps and polluted air. At one point, Koffing was abundant in Galar due to factories. It is most commonly found in urban areas.
Evolution
Koffing evolves into Weezing.
In Galar, it evolves into Galarian Weezing.
(Source: Bulbapedia)










