mtg jumpstart booster box Foundations - Each The Brothers’ War Draft Booster contains 15 cards and 1 token/ad card Magic: The Gathering - Avatar:

While I don't see this being the most expensive Crystal price-wise (that honor goes to The Earth CrystalThe Earth Crystal), I can certainly see this being one of the most widely adopted across multiple archetypes

Murders at Karlov Manor There are a few strong standout cards in Murders at Karlov Manor booster packs

Chart shows the price of Friend Like Me #160 at the end of each month going back as long as we have tracked the item.

PSA Gem Mint 10 sets plus the Mickey Mouse promo have been selling for increasing amounts on eBay since release

Even once its equipped, it feels pretty slow compared to other powerful Equipment like Embercleave