Which Greninja-EX do you have?
Same name, 155× the price: $2.08 to $323 raw. The difference is printed on the card — it is just not somewhere most people think to look.
Twilight Masquerade · #214
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.
$323
44% gem
Crimson Haze · #090
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.
$219
85% gem
Scarlet & Violet Promos · #132
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.
$99
39% gem
XY Promos · #021
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.
$60
71% gem
Twilight Masquerade · #198
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.
$16
36% gem
XY Black Star Promos · #XY20
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.
$9.25
10% gem
Crimson Haze · #083
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.
$8.49
93% gem
Scarlet & Violet Promos · #054
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.
$6.33
12% gem
Twilight Masquerade · #106
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.
$5.25
52% gem
Crimson Haze · #045
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.
$2.08
92% 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.