I have some unlimited editions of almost all BW and XY era Japanese sets in my collection, but only a couple and most cards I have from that era are in 1st edition
Looking at the most valuable cards in the Final Fantasy x Magic: The Gathering set as of the time of writing shows that the highest-value cards are all either foil or surge foil printings, which seems to have contributed to the hyper-inflated cost of both individual Collector Booster packs (now going for $100 on the secondary market) and a Collector Booster Display Box (fetching up to $1,200)
as long as youre playing within the confines of the Rule 0 talk, anything goes
You also get to do all of that while still just curving out on your opponents, which is the other thing I like so much about this deck
What are their reasons for playing
The reality tends to be more uneven, with lower-quality spells hopefully doing enough to maintain momentum as you dig for highly broken outliers like Jeskas Will, Peer into the Abyss, and Ad Nauseam