You can tell the rarity by the number of straight sides the icon has: the more straight sides, the rarer that card, starting from the circular common up to the pentagonal legendary rare
The cards have naturally been assigned magic mana colors, with the Earth Crystal associated with green, the Water Crystal blue, the Fire Crystal red, and the Wind Crystal white
Theyre identical to actions in almost every way: theyre one-off effects that you can play by paying ink
Firstly, people buying just to pull expensive cards and resell the remaining packs will be discouraged
Emet-Selch's last ability checks your graveyard at the moment it would trigger to see if you have fourteen or more cards in your graveyard
Both of these cards have incredibly powerful effects to begin with, but when you consider they can also be sung for free, then they get even more nutty