Always buy graded copies from PSA, CGC, or BGS for No Rarity, CoroCoro, and Illustrator-tier cards, since raw sales at these price points carry too much authentication risk.
Nab a Cheryl (Battle Styles)
Chainer, Dementia Master Theres no shortage of mono-black value machines that return stuff from your graveyard to the battlefield, but Chainer, Dementia Master is one of the originals
For example, Firion, Swordmaster is right at home in Red/White Equipment decks, Astral Titan is great in Red/Green Landfall and Blue/Green towns, and Dawn Warriors Legacy is great in the two spell decks Blue/Red and Black/Red
5 Beluna Grandsquall Adventure is a strong returning mechanic in Wilds of Eldraine , meaning the addition of all these Adventure cards has finally made an Adventure-centric Commander deck viable
Buy singles if you want a specific card Singles are best when: You want one chase card (no gambling on packs)