Gengar is a Ghost/Poison-type Pokémon known for its mischievous and sometimes sinister nature. It evolves from Haunter and is the final form of Gastly. Recognized by its dark purple color and sinister grin, Gengar can hide in shadows, allowing it to stealthily follow people and Pokémon alike. In the Pokémon series, Gengar often plays the role of a challenging opponent in battles due to its high speed and special attack stats. It has a Mega Evolution and a Gigantamax form, showcasing its popularity and power.