Ancients' Leyline

If Ancients' Leyline is in your opening hand, you
may begin the game with it on the battlefield.
At the beginning of your precombat main phase,
search your library for a basic land and put it
into play tapped, then shuffle your library.
Landfall - Whenever a land enters the
battlefield under your control, add 1 mana of
any color to your mana pool.