As you collect duplicate cards, they contribute to your Vault, which, when filled, provides you with Wildcards and other rewards
I have a feeling quite a few tight games are going to end with your opponent playing two copies of Thievery out of nowhere
For example, if your deck has no-holds-barred power despite playing zero Game Changers, then you should play in Bracket 4
But to do this, you must make specific settings and follow the rules
The list of powerful generals is increasing with every new set release, especially as Wizards of the Coast designs more format-friendly cards
It costs four, is an enchantment, and it's a Propaganda/Ghostly Prison for each attacker, but this time they've got to pay mana equal to your domain count...so any deck from three colors on up should run this