For individual cards and older booster packs and boxes, you will just have to gain a lot of experience and learn the nuances of real Pokemon products and then make educated purchases, ideally with a means of recourse if it turns out you were scammed (some kind of buyer protection program, etc)
The newly chosen Size will overwrite the original Catch of the Day's power and toughness, but the newly chosen Keyword and Whenever this creature attacks abilities will be added on top of any copied abilities
10 Conversion Apparatus Mana, Energy, Back To Mana This Artifact makes itself useful while you're working on gathering up a pool of mana and Energy counters
This exclusive bundle includes six booster packs from the highly anticipated Scarlet & Violet expansion, delivering an exciting assortment of cards to enhance your Pokmon TCG collection
[3] I am using the variable names in R's hypergeometric distribution functions (specifically the dhyper function) in my description of the function to assist in reading the R code and because I like the R variable names more than wikipedia's variables (N, n, K, and k)