Perhaps the experience with new cards in Modern Horizons left Wizards feeling a little burned, or perhaps they only intended to leave Masters sets on the shelf for a short time, but it only took a year and a half for Masters sets to make their return with Double Masters this August.
(Source) In total, that means we could look at 63 million Legends cards
Spend 30 minutes or an hour breezing through the tutorial and completing missions and open all the packs you can
Huntmaster of the Fells I know, I know, I just said Werewolves don't have a monopoly on transformation, but they're really good at it, and this particular Innistrad Werewolf is about as good as it gets
I think of Ghalta when I think of 12 Mana
This card's only downfall is the expensive Retreat Cost of three energy