The best case for all of these cards is probably Edric, Spymaster of Trest, which held steady at around $4 with very fringe legacy play, until it ended up winning a SCG open last April and spiked to $15 overnight (before getting reprinted in Conspiracy a few months later and dropping dramatically)
I still believe these price points are too low for an item that is only printed 100 copies (technically each copy is unique as well)
Pairing it with mass discard spells like Windfall or Dark Deal creates explosive turns where you wipe opponents hands while flooding the board and refilling your own resources
Yes, he comes down slower than Karn, and yes, he doesnt do certain things that O-Stone does
Still Life with a Skull and a Writing Quill by Pieter Claeszoon (1628)
Theres also a fun flavor piece with Shadowfax which tells players the meaning of haste, an evergreen mechanic that isnt typically explained on a card, a fun reference when Gandalf says to Shadowfax, show us the meaning of haste.