Gengar

Gengar, also known as the Shadow Pokémon, is a Ghost/Poison-type Pokémon. It is the third and final evolution in the Gaseous Pokémon family, evolving from Haunter when traded with another Pokémon Trainer.

Pokédex Data
Gengar has a roundish body of dark-purple colouration. It has stubby arms and legs, spines running down its back to its tail, two red eyes and a wide mouth filled with white square teeth. It nearly always has a malicious grin on its face.

Gengar are known to reside in abandoned buildings and dark caverns, sometimes even appearing in forests after dark. They are rarely seen in the wild at all, largely due to their ability to blend in with the shadows as they stalk unwary victims. Their presence can be felt, however, as the area around them cools due to their bodies absorbing the surrounding heat.

Like Gastly and Haunter, Gengar enjoys scaring people and playing pranks, eg. taking the form of a person's shadow and behaving erratically. Though often conceived as being sinister, Gengar can be extremely loyal to Trainers that treat them well.

Abilities

 * Night Shade - Gengar strikes its opponent with a wave of dark energy. This attack always hits and causes damage regardless of the opposing Pokémon's type.
 * Lick - Gengar slurps its opponent with its long tongue, afflicting them with paralysis.
 * Will-O-Wisp - Gengar casts spectral blue flames that afflict the opponent with a burning curse.
 * Sucker Punch - As the opponent readies an attack, Gengar acts first and launches a surprise attack.

Mega Evolution
Gengar can be transformed into Mega Gengar using the Mega Stone Gengarite. In its Mega form, Gengar develops a yellow third eye on its forehead and its ears and spines grow longer. Additional spines also erupt from its tail and its forearms and its lower body takes on a reddish hue. In its Mega Form, Gengar becomes more aggressive and is likely to attack its own Trainer as well as an opponent.

The Mega Evolution is temporary and only occurs during battle if the Trainer is carrying a Mega Ring and the Gengar holds the corresponding Mega Stone.

Gigantimax
In Gigantamax form, Gengar becomes larger, with portions of its body sinking into ground, and only the head, tail, and arms remain. Its body changes from dark-purple to light-purple, and its eyes become white with yellow sclera. The inside of its mouth changes to resemble a tunnel with a long purple tongue sticking out. Three red clouds surround the top of Gengar's head.

Gigantamax Gengar's mouth is rumored to not lead into its body. Due to the cursed energy, it is believed to instead lead into the afterlife. By laying a trap, it attempts to steal the lives of those it captures. Should someone stand near its mouth, they can hear the voices of their loved ones calling out to them. Gigantamax Gengar is the only known Pokémon capable of using the exclusive G-Max Move G-Max Terror.