Pokmon cards are collectible, sure but they are also the base of a competitive strategy game played by millions
When sent to GY, it can discard 1 Super Quant card to draw 1 card, which is more useful than its summon effect most of the time.
Gain 2 life, surveil two, make a 4/4, and then draw a permanent card
In episode 5, Yuuki Judai , Marufuji Sho , and Maeda Hayato appeared as cards drawn by Daitokuji , who broke in while playing the game 'Tell a story as scary as the level of the selected monster.' The story Daitokuji told at this time was about a closed dormitory
Now whether you want to track down some of the older releases, pre-re-release is up to you, but if you are going to do it, I highly recommend pretty much everything after and including The Ring Maker cycle but cautioning that you should be ready to wait to finish collections
This is because all Coalossal VMAX needs to function is a few Pokmon and some energy