Shiny Gengar in the middle of mega evolving - Imgur

Mega Gengar (Pokémon GO) - Best Movesets, Counters, Evolutions and CP

Free Pokemon X/Y Shiny Gengar Now Available at GameStop; Diancie Coming Soon - GameSpot

MEGA GENGAR IN MASTER LEAGUE! Pokémon GO Battle League

Hundo Costume Gengar and he can Mega evolve! Does his mega form

Pokemon X & Y: get Shiny Gengar and Diancie at GameStop, GAME UK

Pokemon Card New Mega M Gengar EX - XY166 - Holo Promo

MAX CP MEGA GENGAR EVOLUTION IN POKEMON GO

Mega M Gengar EX XY166 Shiny Black Star Promo Ultra Rare Pokemon Card MINT Values - MAVIN

Shiny Mega Gengar EX HOLO RARE XY166 XY Black Star PROMO Values - MAVIN

New Info?] Looks like Party Hat Gengar will be able to Mega Evolve : r/TheSilphRoad