I had a great time last weekend at the prerelease, enjoying some Two-Headed Giant with my mates and feeling the new mechanics in action for the first time
Each pack contains 12 Japanese-language Magic cards, including 1 Mystical Archive card (Uncommon, Rare, or Mythic Rare), 1 Lesson card (Common, Uncommon, Rare, or Mythic Rare), 1 Rare or Mythic Rare, 1 foil of any rarity, 1 Wild Card of any rarity, 6 assorted Commons or Uncommons that are thematically connected (with Commons connected to other Commons and Uncommons connected to other Uncommons), and 1 Land cardplus 1 Art Card and 1 Ad/Token or special card from Magic's history (a card from "The List")
It supports diverse image styles, including but not limited to sketch, artistic, 3-D, cinematic, and more
What makes them good is that they deal with most of the problems you might face, be that a Baneslayer Angel, a Sword of Fire and Ice or a Moat (well, not Abrupt Decay but you get the point)
Commander players, get ready for some curtailed games next time you face mono-green