Yedora might not have the most powerful ability in the game, dozens of keywords and the ability to go infinite with half of the cards in the game
It all comes down to what matters most to you: Go with PSA if youre after top resale value and worldwide recognition
Essentially, if you have a full party with all four of these on the board, you can pay one white, one blue, and one black mana to give the Warrior lifelink, deathtouch, and make him unblockable (deathtouch and unblockable at the same time has no real use, but thats still OP to think about)
Using removal on the Melded creature card will put both Meld pairs into the graveyard unless specifically exiled
The main reason Standard is so expensive is that fetchable dual lands were printed in the same Standard as fetchlands
Trading cards can teach negotiation and fairness, and organizing a deck of cards requires planning and attention to detail