Blue cards, in general, tend to be highly valued for their efficiency and average low cost to play
It also plays nicely with the myriad of other goblins in the deck (especially flipped Verdict: Good card
But in recent years, Pirovino has redirected his collecting with a much more personal narrative, selling his figurines for many millions of dollars. As an investment, collectibles arent guaranteed to hold value, as anyone who bought into the 90s-era Beanie Babies mania can tell you
I would focus on this as a newer player as you learn about the staples of other formats, which can help decide what you value in trades and which cards are worth trading
Let me know in the comments below, or over on the Draftsim Twitter
The Shiny Vault , in particular, is a secret subset of cards featuring shiny mons