Bristly Bill, Spine Sower

Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature.
{3}{G}{G}: Double the number of +1/+1 counters on each creature you control.

Nissa, Resurgent Animist

Landfall — Whenever a land you control enters, add one mana of any color. Then if this is the second time this ability has resolved this turn, reveal cards from the top of your library until you reveal an Elf or Elemental card. Put that card into your hand and the rest on the bottom of your library in a random order.

Mossborn Hydra

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
This creature enters with a +1/+1 counter on it.
Landfall — Whenever a land you control enters, double the number of +1/+1 counters on this creature.

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards. (They put the top three cards of their library into their graveyard.)

Tatyova, Benthic Druid

Landfall — Whenever a land you control enters, you gain 1 life and draw a card.

Tifa Lockhart

Trample
Landfall — Whenever a land you control enters, double Tifa Lockhart's power until end of turn.

Courser of Kruphix

Play with the top card of your library revealed.
You may play lands from the top of your library.
Landfall — Whenever a land you control enters, you gain 1 life.

Scythecat Cub

Trample
Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature you control. If this is the second time this ability has resolved this turn, double the number of +1/+1 counters on that creature instead.

Tireless Provisioner

Landfall — Whenever a land you control enters, create a Food token or a Treasure token. (Food is an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life." Treasure is an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Aesi, Tyrant of Gyre Strait

You may play an additional land on each of your turns.
Landfall — Whenever a land you control enters, you may draw a card.

Roil Elemental

Flying
Landfall — Whenever a land you control enters, you may gain control of target creature for as long as you control this creature.

Ruin Crab

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)