The simplest answer to this question is that cards that are not only desired but also rare enough to warrant a higher price from lack of supply are worth the most
While I had the same reaction when first seeing Jumbo Cactuar's unique ability for the first time, the difference between 40, 10,000, or infinite damage is fairly negligible when they all have the same outcome by the end of a Commander match
Johnny, Combo Player
Standard / Mill MTG Decks a strategy that attempts to force the opponent to draw from an empty library, thereby losing
Indeed Death's Shadow makes it a perk to nug yourself for 2 in those constructed formats
We also have 40 cards from (MAR) (sometimes called Marvel Universe Source Material ), which are reprints of staples like Counterspell, Reanimate, and Reprieve, but using full comic book art from the comics