Two main factors drive the cost of cards: collector appeal, and demand from competitive players
In my games with it so far, Ive enjoyed mirror versions of Archon of Cruelty, Farhaven Elf, and even Nyxbloom Ancient
DemonDragonJ on Fires of Purgatory 5 years ago I have also replaced Oros, the Avenger with Mathas, Fiend Seeker , which reduced the average converted mana cost of this deck even further from 4.16 to 4.11, because, as much as I wish to have all ten primordial dragons in my EDH decks, Oros simply does not work with the strategy of this deck, but Mathas very much does, so he is a welcome addition to this deck
at least I didn't mention the SpongeBob one!) I know that it's hard to surpass the original, iconic design by Mark Poole, but to me, nothing encapsulates the frustration of getting a key spell countered like being slapped in the face