There aren't many truly valuable cards from seven different sets so far (not double-counting for base and foil releases), but there are some standouts if you were lucky enough to get in on the Ghost of Tsushima drops
Based on our rule that with an average CMC of 2.5, you need at least 25 lands in your deck, I would estimate that the Gr Devotion list would want around 29 lands to function optimally
A cycle of five cards were introduced, one for each color, which means black was given its first and only soulbond creature, Doom Weaver
Look at some of the current decks in Brawl, and land counts dont get too low
To determine the total cost of a spell, start with the mana cost or alternative cost (such as a miracle cost) you're paying, add any cost increases, then apply any cost reductions
But today one of the first things you look at when you see a new card is probably the creature type