Memory Erosion is one of the most annoying yet satisfying enchantment additions you can make to a mill deck
3 Hisuian Arcanine: Lost Origin (Trainer Gallery) $0.85 A Candidate For Future Greatness While it's not one of the most expensive cards in Lost Origin, this Trainer Gallery artwork features a gorgeous scene between this Hisui native and Rei, a member (the main character) of the Survey Corps
R Rare True King Lithosagym, the Disaster X EARTH Level 9 [ WyrmEffect ] ATK 2500 DEF 2300 If this card is in your hand: You can destroy 2 other monsters in your hand and/or face-up field, including an EARTH monster, and if you do, Special Summon this card, and if you do that, and both destroyed monsters were EARTH, you can also look at your opponent's Extra Deck and banish up to 3 monsters from it with different names
That said, if CoP: Red were Standard legal on Arena, dont you think people would be packing it to climb the ladder
Although some particular vintage cards might be able to sell for large premiums, they are very hard to come by
