Which Slowpoke 1st Edition do you have?
Same name, 63× the price: $2.40 to $152 raw. The difference is printed on the card — it is just not somewhere most people think to look.
Pokémon Web · #012
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.
$152
62% gem
Wind from the Sea · #031
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.
$67
50% gem
Flight of Legends · #044
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.
$18
30% gem
Rocket Gang Strikes Back · #040
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.
$17
38% gem
Dark Rush · #016
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.
$5.19
44% gem
Golden Sky, Silvery Ocean · #040
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.
$5.16
54% gem
Rage of the Broken Heavens · #013
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.
$4.62
79% gem
Holon Research Tower · #022
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.
$3.60
52% gem
HeartGold Collection · #017
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.
$2.40
51% 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.