Omnath, Locus of Creation

When Omnath, Locus of Creation enters the
battlefield, draw a card.
Landfall — Whenever a land enters the
battlefield under your control, you gain 4 life
if this is the first time this ability has resolved
this turn.
If it's the second time, add {r}{g}{w}{u}.
If it's the third time, Omnath deals 4 damage
to each opponent and each planeswalker you
don't control.