extremely rare yugioh cards 10 of the most expensive Yu-Gi-Oh! of all time The 12 Most Expensive Yu-Gi-Oh!

That said, they also have the least amount of impact on the game

Junk Signal X SPELL Quick-Play Activate 1 of these effects (also you cannot Special Summon from the Extra Deck for the rest of this turn, except Synchro Monsters)

Whilst some cards in poorer condition wont bring in the big bucks, below are some rare Charizard Pokmon cards that have sold for great prices Charizard Crystal Holo Skyridge (Image sourced from PSA website) In one case, this 2003 card was authenticated to Grade 9 by the PSA

The only downside is that you can only Special Summon Water Monsters for your next two turns not really a problem for Water-based decks