Gastly is a fictional creature from the Pokémon games. It appears in Smash Run in Super Smash Bros. for 3DS
In Super Smash Bros. 3DS/Wii U
Gastly appears as in an enemy in Smash Run, the only way to hit it is with a non-physical attack (Like Lucario's aura sphere), but Gastly can be found with a Yellow Ghost from Find Mii 2 and will try to block the attacks with its shield
This Ghost/Poison-type Pokemon is made up several toxic gases--touching it would be really unpleasant. Instead, try to take it out with projectiles. It's not the fastest enemy in Smash Run, but occasionally it may try to chase down a fighter, so be careful around this gaseous foe.
Gastly is a First-Gen Ghost/Poison type Pokémon that first appeared in the Pokémon Red, Blue & Green games. It evolves into Haunter at level 25, and then into Gengar through link trade. Its Pokédex number is #092.