Grading involves a professional inspection of your cards condition, assigning a numerical grade based on factors such as centering, corners, edges, and surface
A Venusaur pokemon card, the big plant pokemon with flowers on its back, pokemon card coloring page
Since nearly every Pokmon deck runs basic Energy cards, theres a decently high floor for the demand from collector-players for high-rarity Energy cards that match the other high-rarity cards in Standard, even when all the other cards in a set are lackluster
The commander version of casual rares and mythics follow the typical price trajectory of newly release cards - starting off high in value, usually pre-selling for at least half of their original versions, and then dropping in value as more and more commander decks are opened
Ghost / Phantom Stamps Some 1st Edition cards have a faint, partial, or grey "Edition 1" stamp instead of a clean black one, caused by ink transfer between sheets during the stamping process