The Pokémon TCG hides Mega Gengar in the background art of 1 card. The cameos sit across 2014, with 5ban Graphics responsible for several of them.
These cameos cluster in Phantom Forces most heavily; 5ban Graphics accounts for 1 of the appearances.
These cards feature energy loops, abstract background, purple and glowing eyes in their background art, illustrated by artists like 5ban Graphics.
Mega Gengar appears as a background cameo across 1 Pokémon card.
These appearances range from clear sightings to barely-visible silhouettes, scattered across 2014 of the TCG.
Each cameo rewards collectors who pause to look closely at the card art.