Getting Gengar used to be all about trading. But in this single-player Pokemon game, there's a new way to evolve Haunter...
Earn 70 hearts with your Buddy Pokémon: Allows Eevee to be evolved into Sylveon. Trade Evolution: Evolves Kadabra into Alakazam, Machoke into Machamp, Graveler into Golem (including Alolan form), Haunter into Gengar, Boldore into Gigalith, Gurdurr into Conkeldurr, Karrablast into Escavalier, S...