Retreat to Kazandu

Landfall — Whenever a land you control enters, choose one —
• Put a +1/+1 counter on target creature.
• You gain 2 life.

Retreat to Coralhelm

Landfall — Whenever a land you control enters, choose one —
• You may tap or untap target creature.
• Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Tatyova, Benthic Druid

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

Zendikar's Roil

Landfall — Whenever a land you control enters, create a 2/2 green Elemental creature token.

Ob Nixilis, the Fallen

Landfall — Whenever a land you control enters, you may have target player lose 3 life. If you do, put three +1/+1 counters on Ob Nixilis, the Fallen.

Ancient Greenwarden

Reach (This creature can block creatures with flying.)
You may play lands from your graveyard.
If a land entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Scute Swarm

Landfall — Whenever a land you control enters, create a 1/1 green Insect creature token. If you control six or more lands, create a token that's a copy of Scute Swarm instead.

Lotus Cobra

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

Azusa, Lost but Seeking

You may play two additional lands on each of your turns.

Yarok, the Desecrated

Deathtouch, lifelink
If a permanent entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Retreat to Hagra

Landfall — Whenever a land you control enters, choose one —
• Target creature gets +1/+0 and gains deathtouch until end of turn.
• Each opponent loses 1 life and you gain 1 life.

Scapeshift

Sacrifice any number of lands. Search your library for up to that many land cards, put them onto the battlefield tapped, then shuffle.

Avenger of Zendikar

When Avenger of Zendikar enters, create a 0/1 green Plant creature token for each land you control.
Landfall — Whenever a land you control enters, you may put a +1/+1 counter on each Plant creature you control.