Gastly is a Ghost/Poison-type Pokémon introduced in the first generation of the Pokémon series. It is known for its round, floating body made of gas, which gives it a spooky appearance. Gastly has large, expressive eyes and a mouth that often appears to be smiling. It is known for its ability to envelop opponents in its gas, causing confusion and fear. Gastly evolves into Haunter at level 25 and can further evolve into Gengar when traded. It is commonly found in haunted locations and is known for its playful yet mischievous nature. Gastly is often used in battles for its unique type combination and special abilities.