It would have been amazing as a unicorn with Flying
Core Set 2019 will probably not have as many this could be $1 or it could be $30 cards as Dominaria did, which makes it a worse set for bulk or near-bulk speculation
However, they are widely accepted for "kitchen table" casual play, playtesting decks, and Cube drafts, provided they are clearly marked as proxies and not sold as authentic cards
Promos are definitely a stay-away for now, as everyone is listing theirs for at least $5 (foils at $10!), and that price has to come down some for anything good to happen
Including Booster Boxes, Tins, Collection Boxes, and Booster Packs
You get what you see, make sure to double click on images to zoom in and verify sharpnessWrath of GodCondemnMortifyPsionic BlastCruel EdictDisenchantRecollect