Which Mega Gengar do you have?
Same name, 338× the price: $3.24 to $1,094 raw. The difference is printed on the card — it is just not somewhere most people think to look.
Ascended Heroes · #284
Check the set symbol in the lower right of the illustration, and the copyright year along the bottom edge. Those two identify the print run on every card that has them.
$1,094
63% gem
Mega Dream · #240
Check the set symbol in the lower right of the illustration, and the copyright year along the bottom edge. Those two identify the print run on every card that has them.
$294
89% gem
Mega Dream · #230
Check the set symbol in the lower right of the illustration, and the copyright year along the bottom edge. Those two identify the print run on every card that has them.
$25
91% gem
Ascended Heroes · #125
Check the set symbol in the lower right of the illustration, and the copyright year along the bottom edge. Those two identify the print run on every card that has them.
$3.58
77% gem
Phantasmal Flames · #056
Check the set symbol in the lower right of the illustration, and the copyright year along the bottom edge. Those two identify the print run on every card that has them.
$3.24
61% gem
We have no hand-checked note for these printings yet, so the guidance above is the general rule rather than something specific to this card.
Prices are raw market value. Click a printing for its full grading verdict — the gem rate, the fees and whether it beats selling raw.