Forget Griselbrand drawing you seven a turn, Kefka turns every source of life loss into a card draw spell
This four cost Amethyst card has a relatively straightforward ability, when it comes in to play, you draw a card
This means if a deck is built with Ruby and Amethyst cards, it cannot contain cards from Emerald or the other ink types
You must pay its mana cost (or, if another effect allows, an alternative cost)
A spell cast using flashback will always be exiled afterward, whether it resolves, is countered, or leaves the stack in some other way
There is also a companion mobile app featuring a complete card catalog, where players can keep track of their card collections and wish list of cards they hope to add to their deck