I believe this is valid because silver border, now acorn, gives the entire team, design, play, world building, art direction, marketing and everything in between, artists, players, and article writers a chance to go out to the very edges of what the game could do
Its monocolor, instant speed, gets you back any previously-milled threat, and has some pretty significant interactions with other powerful spells including the number one self-mill effect on our list 1
(Equipment, Auras you control, and counters are modifications.) : Create a 5/5 red Dragon Spirit creature token with flying
Coming later this year to WPN Premium stores, these promos will arrive quarterly and aren't tied to any specific event or promotion: stores can make these promos available however it best suits their needs
Sources that have no creature type at all are non-Human sources, as are sources with creature types that dont include Human
Until then this card is way too narrow and only filler when it does get a slot making it not A cube material