Yu-Gi-Oh!

The rarity and the set code are what separate a common from a chase card.

Yu-Gi-Oh! prints the same card at many rarities inside one set, and the rarity is most of the value.

Common, Rare, Super Rare, Ultra Rare and Secret Rare are different cards as far as the market cares. Tick the one on your card.

The set code

The code in the corner, like LOB-EN005, names the set and the number in one string.

A clear scan of that corner is worth more than a clear scan of the art.

1st Edition, Unlimited and Limited Edition sell for different money on older cards. It is printed under the artwork.