When Omnath enters, draw a card. Landfall — Whenever a land you control enters, 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.

You may play an additional land on each of your turns. {4}{G}{G}, {T}: Look at the top six cards of your library. You may reveal a creature card with mana value less than or equal to the number of lands you control from among them and put it onto the battlefield. Put the rest on the bottom in a random order.

This land enters tapped. {T}: Add {G} or {U}.

Trample Landfall — Whenever a land you control enters, you may create a 4/4 green Beast creature token.

You don't lose unspent green mana as steps and phases end. Omnath gets +1/+1 for each unspent green mana you have.