The all-yellow card are a variation of “filler” card and have been around since the early WOTC era… I can’t speak to this exact copy since I don’t have it in hand, and it’s hard to judge based on photos, but finding another filler card copy isn’t very surprising as I’d imagine plenty came into circulation. The last copy I saw sold for around $80 this past year.
I just love the pokemon artwork, doesn’t make sense to me to buy “blank” cards (& as far as i know these filler cards were not available for the e-series; my main collection focus) + if there were any theres no way to distinguish 'm from other fillers anyways [again; as far as i know]
Also; the sample & FPO cards set me back far enough, really hoping there isn’t more elusive stuff like this that i still gotta add to the collection
I have been working on an updated E4 error guide for awhile now and will post it sometime before the end of this month. But the short of it is:
Blank (potential counterfeits floating are around)
Partial left side border (solid yellow)
Partial right side border (solid yellow)
Solid yellow border
Solid yellow blank card
E-card blank (first I’m hearing of one being circulated by Rusty)
Gray-scale Pokéball filler card
Graduated yellow borders (post 2005 or so)
Graduated right side yellow border
Graduated left side yellow border
WC partial and full bordered blank cards
Any blank holo cards are difficult to authenticate.