Madness is such a strong effect as it turns discarding, something that can be a downside, into extra value with a discounted spell
Even with their differences, each party may want to know some of the most expensive cards so that when cracking packs or looking for singles they can instantly know if their purchase is worth it
Sword of Feast and Famine is definitely a favorite, too: The moody sky, the glowing moon, and the fact that you can untap all of your lands by dealing damage to an equipped creature make it viable just about anywhere
Suspend cards often have lower costs to suspend then they would otherwise have through their regular casting costs to balance the downside of waiting to cast it
No, once your creature attacks a planeswalker, you cannot direct the damage to the player
I always complain about how little black targetted discard there is