The only card that is truly guaranteed to sell for a decent amount is the Mewtwo typo from the original movie about funny characters
Weakness: Grass (x2) Resistance: none Retreat: 3 Vullaby - Darkness - HP70 Basic Pokmon [C] Playful Kick: 10 damage
Commander-focused foils are still doing quite well, and there hasnt been a meaningful dip in that market since the Collector Boosters were first previewed
Number 116 Language English Legal Formats Commander, Legacy, Modern, Vintage Not Legal Formats Alchemy, Brawl, Competitive Brawl, Historic, Pauper, Pioneer, Standard, Timeless Rulings (12/7/2018) You don't have to choose the name of a card that's still in your library, or even a card that's in your deck at all
Its not nearly as restrictive because you can just play more cards
The earliest version acted like a Leyline that had an effect if you drew it in your opening hand