For the physical collectors, they release alchemy cards, which exclusively appear on the online service and bolster what synergies and card combos can be found when playing digitally
A good start includes 35-39 lands and a handful of rocks, though certain decks (particularly artifact-focused ones like Breeches, the Blastmaker or Slobad, Iron Goblin) will play more
Between the +1/+1 counters and indestructibility, I except it to always kill an opposing creature in combat or counter a removal spell on top of drawing a card
Consider it a great friend of the Courser above
This release features a rather interesting set of mythics this time around
One mythic can flood you with mana, bury your opponent in card advantage, and threaten to end the game on the same turn