Shadow crystals ?

Hi,
what is the best use of shadow crystals ? Booster packs and which ? Or decks ?
Thanks in advance.

depends if you start or not.
for starters some decks give you a coherent set of cards, some with very valuable ones, so it's better.
i think raphael majere had a guide for beginners

if you've been around for a while, focusing on card sets you dont have is probably best.

Yes i'm just starting.
I read the beginners guides but apart from tainted magic (eladwen deck) and raikka's deck (sell for gold) they are not other advices for the other sets. That's why i ask.
Thanks for the answer.

That’s pretty much all there is too it

Nobody has done a comprehensive breakdown of the sets lately but I do t think there is anything big that has changed