Garnet, Princess of Alexandria A solid 2/2 for 2 with lifelink, Garnet shines it up by her interaction with Sagas by keeping them around longer and growing, working especially well with Saga creatures
They are calling this the rarity key, and the rare, super rare and legendary symbols will be holographic on the cards (or some kind of shiny gradient), to make it even easier to differentiate
I tried out different numbers and amounts of life loss, but the Sleeper Agent problem was quite real here: it was hard to get this at a rate where it was fun while encouraging you to keep it or give it away in different games
Soulherder shoehorns you into offering some support for Blink decks, but the options here are slim and most Cubes are going to feature creatures worth blinking anyway
I will test out all the cards not already in cube and getting a 6 or higher rating except for Tragic Slip which has already had a good amount of recent cube action
Spending a measly 1 mana to blank every copy of Counterspell, Force of Will, and Fierce Guardianship in your opponents decks is one of the best exchanges you can make