Akoum Hellhound

Landfall — Whenever a land you control enters, Akoum Hellhound gets +2/+2 until end of turn.

Phylath, World Sculptor

When Phylath, World Sculptor enters, create a 0/1 green Plant creature token for each basic land you control.
Landfall — Whenever a land you control enters, put four +1/+1 counters on target Plant you control.

Lotus Cobra

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

Hydra's Growth

Enchant creature
When Hydra's Growth enters, put a +1/+1 counter on enchanted creature.
At the beginning of your upkeep, double the number of +1/+1 counters on enchanted creature.

Mountain

Spitfire Lagac

Landfall — Whenever a land you control enters, Spitfire Lagac deals 1 damage to each opponent.

Canopy Baloth

Landfall — Whenever a land you control enters, Canopy Baloth gets +2/+2 until end of turn.

Kazandu Nectarpot

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

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

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.

Azusa, Lost but Seeking

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

Territorial Scythecat

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Landfall — Whenever a land you control enters, put a +1/+1 counter on Territorial Scythecat.