Just a heads-up, though some chests might have older booster packs, which isn't everyone's cup of tea if you're chasing newer cards
These are alternate art variants of cards at different rarities
Remember, the cards you put up for trade should be the same rarity as the ones that you need, so if you're chasing an ex card, you'll need to offer up an ex card of your own as part of the trade
Some of them have two new designations, daybound and nightbound
Foil Magic the Gathering cards have been a part of the game since the release of Urzas Legacy in 1999, and have been tinkered with ever since, from the shooting star image used in the early iterations, to foil-etching in Commander Legends, to every kind of Magic the Gathering Foil you can imagine
The cards I am attached to in YGO are the cards I remember playing with