The best checker starts with a clear card photo, identifies the Pokemon, set number, rarity, edition, language, and condition, then compares recent sold prices rather than active listings only
It's sort of like a different take on Niv-Mizzet Reborn
Then if this creature didnt transform this way, you lose the game
A Pokmon card is valuable based on several factors, including its age, eligibility, what set it was released in, the physical quality or condition of the card, the rarity and desirability, and the Pokmon/character/item that is featured on the card
Rereleased cards aren't worth anything like the original vintage card, but they are still very popular today