Though I'm kicking myself very hard for selling all my cards ages ago. 😵😅

OMG! Same here. I sold about 60k DEC worth of Alpha/Beta/Rewards cards about a month before the SPS airdrop. I had no idea. Good thing I got lazy and held on to rest of my collection. But I lost some pretty good cards there. Lol!

Now I'm re-learning the game, too.