(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When this Siege enters, create X 2/2 white and blue Knight creature tokens with vigilance.
[+1]: Draw two cards. Then discard two cards unless you discard a creature card.
[−2]: You get an emblem with "Knights you control get +1/+0 and have ward
."
[−3]: Tap any number of untapped creatures you control. When you do, shuffle target nonland permanent an opponent controls with mana value X or less into its owner's library, where X is the number of creatures tapped this way.