Naturally, being a Trading Card Game, its a little more complicated than just picking and choosing the exact cards you want or need for your deck
Move all damage counters from all other characters to that character
These arent mechanically different to other cards with the same name in the Rise of the Floodborn set, but instead are visually spectacular and very hard to find alternate art variants
As you can likely tell by the card, his true form turns out to be the primal Hades, and given his intense nostalgic living in the past, it makes sense that he'd have a Yawgmoth's Will-like effect
Showcase Treasures Extended art and foils feel premium
Mix all of that together, then add a sprinkling of the stock problems that publisher Ravensburger had with The First Chapter, where demand far exceeded supply for several months after release, and you have the perfect recipe for very valuable cards indeed