Generally speaking, Magical Stone Excavation is a bad card because you're trading 3 cards (itself, and the two you discard) for just 1 card back, costing you 2 cards in the process, although this isn't true for all cards since the card One for One (quite ironically, a 2 for 1) will always generate advantage, despite technically always costing you a card since you could potentially summon something like Glow-Up Bulb which can recur from the grave at no cost your hand or field, effectively replacing the card you discarded for One for One while also (going back to point 1) progressing your gamestate by helping you make easy Synchros
This method is the fastest, although you may lose some potential revenue if you do so
Figure out what your personal metagame is like and run the cards that thrive in that specific environment or just cram in whatever blue instants/sorceries you have on hand and go to town, up to you
You cant just trade cards willy-nilly in this game, because otherwise it would be too easy to get a full collection (and the Pokmon Company would lose microtransaction money, of course)
