Just buy the one product, ignore the collectible part, and use it as a self-contained environment
It doesnt let you ignore format legality
In High Class Packs like MEGA Dream ex, MA cards pull at approximately 1 per box
Many of these cards show off gorgeous artwork and snazzy holographic touches that make them pop in any collection
In terms of price, Cavern of Souls goes for around $50 at the low-end of sales, but the card is starting to uptick towards $65 in both versions
However, if your mission statement as a casual player is play as many unique and enjoyable games as possible, then at least having an open mind and a 1v1-oriented deck will lead to playing games you otherwise wouldnt both in how those games play out and the actual literal opportunity to play them