William, the Blightcaller

When William, the Blightcaller enters the battlefield, for each opponent, target land they
control becomes a Barren land with {t}, Sacrifice
this land: Add {1} and loses all other card types and abilities.
When William, the Blightcaller deals combat
damage to a player, that player discards a card. If
they cannot, target land that player controls
becomes Barren.