Shalvon, the Leaftithe

Whenever a land enters the battlefield under an
opponent's control, choose one that hasn't been
chosen yet this turn:
• You gain 2 life.
• You may put a land card from your hand onto
the battlefield.
• Reveal the top card of your library. If it's a
land card, put it into your hand. Otherwise put
it on the bottom of your library.