The Master of Keys The Master of Keys is a cellarspawn who is able to use the House's doors as thresholds not just between adjacent rooms but unconnected rooms as well
You have card advantage for grindy games, lifegain against aggro, the ability to enable all your infusion cards immediately, and removal
(3/19/2021) If the target spell is face down, it'll be exiled face up
It's way too easy to make treasures for how cheap this card is, and getting to turn those into Dragons is a scary prospect
In this case, sacrificing a creature nets you two black mana, which is a useful ability in a wide variety of decks, and it represents the color black perfectly
If the customers found out stores didnt receive anything until a week later, then it would kill the generated excitement at the top of the marketing tentpole