Omnath Locus of Creation

“When Omnath, Locus of Creation enters the battlefield, draw a card. <br> <em>Landfall</em> — 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 RGWU. If it's the third time, Omnath deals 4 damage to each opponent and each planeswalker you don't control.”