card sleeve envelopes Guardian Key Holder Sleeves, Pack of 500 Small for Hotel Key Cards, Gift Cards, Credit Cards, and More, 2 ⅜ Inches x 3 ½ Inches, Black : Office Products minimalist style perfect for birthdays Credit Card Sleeve (2 3/8

Card Size is Different Paper Quality difference and Paper Thickness, but this depends on the set too I think, because they may change the paper stock that they use depending on cost of materials you can also ask a Pokemon Professor, they may have insight into fake cards entering the market and be able to give you pointers in spotting fakes

One of four mew Trainer Cameo I believe

How to play a Pokmon V-UNION: Once per game during your turn, combine 4 different Morpeko V-UNION from your discard pile and put them onto your Bench

Quattro (Duel Generation) Quattro is a Duelist Construct of Quattro from the Yu-Gi-Oh