Every Misty's Horsea card we price, most valuable first. Prices are what copies actually sold for, updated daily.
What a Misty's Horsea card is worth
The most valuable Misty's Horsea on this list is Misty's Horsea from Gym Heroes at $3.35£2.51€2.92, and the 2 priced copies across 2 sets are worth $6£5€5 together. Most of that sits in a handful of printings: the older the set and the scarcer the print run, the wider the gap to the rest.
Misty's Horsea is printed in Japanese as well: 3 cards across 2 sets, the most valuable of them Misty's Horsea from City Gym Decks at $2.92£2.19€2.55. Switch the list above to Japanese to read those, or to Both to rank the two catalogues against each other.
The highest PSA 10 on record for Misty's Horsea sold for $503.50£377.32€439.35. 1st Edition printings are priced separately from the standard card, because they do not trade at the same money.
If you are trying to identify which Misty's Horsea you have, the set name is printed on the card and the collector number sits in the bottom corner. Open the card here and the page carries every printing of it, the graded prices, and whether grading the copy is worth the fee. Sets to start with: Gym Heroes, Gym Challenge.