Mangara, the Diplomat

If a spell or ability an opponent controls causes you to discard a card, you may reveal that card and put it on top of your library instead of putting it anywhere else. T: Add C.

Swarm of Rats's power is equal to the number of Rats you control.

As an additional cost to cast this spell, discard X land cards. Destroy X target lands.

Vigilance When this creature enters, for each opponent, choose a creature with the greatest power among creatures that player controls. Destroy those creatures.

1R, T: Destroy target artifact. This creature deals damage to that artifact's controller equal to the artifact's mana value.

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Blue creatures you control can't be blocked.