Rampaging Baloths

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

Sakura-Tribe Scout

{T}: You may put a land card from your hand onto the battlefield.

Ulvenwald Behemoth

Trample, haste
Other creatures you control get +1/+1 and have trample and haste.

Ulvenwald Oddity

Trample, haste
{5}{G}{G}: Transform Ulvenwald Oddity.

Ulvenwald Oddity // Ulvenwald Behemoth

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.

Case of the Locked Hothouse

You may play an additional land on each of your turns.
To solve — You control seven or more lands. (If unsolved, solve at the beginning of your end step.)
Solved — You may look at the top card of your library any time, and you may play lands and cast creature and enchantment spells from the top of your library.

Skyshroud Ranger

{T}: You may put a land card from your hand onto the battlefield. Activate only as a sorcery.

Lotus Cobra

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

Bonny Pall, Clearcutter

Reach
When Bonny Pall, Clearcutter enters, create Beau, a legendary blue Ox creature token with "This creature's power and toughness are each equal to the number of lands you control."
Whenever you attack, draw a card, then you may put a land card from your hand or graveyard onto the battlefield.

Wayward Swordtooth

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
You may play an additional land on each of your turns.
Wayward Swordtooth can't attack or block unless you have the city's blessing.

Llanowar Scout

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.)

Exploration

You may play an additional land on each of your turns.

Azusa, Lost but Seeking

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

Tatyova, Benthic Druid

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

Crashing Drawbridge

Defender
{T}: Creatures you control gain haste until end of turn.

Concordant Crossroads

Dryad of the Ilysian Grove

You may play an additional land on each of your turns.
Lands you control are every basic land type in addition to their other types.

Ovinomancer

When Ovinomancer enters, sacrifice it unless you return three basic lands you control to their owner's hand.
{T}, Return Ovinomancer to its owner's hand: Destroy target creature. It can't be regenerated. That creature's controller creates a 0/1 green Sheep creature token.

Oracle of Mul Daya

You may play an additional land on each of your turns.
Play with the top card of your library revealed.
You may play lands from the top of your library.

Druid Class

(Gain the next level as a sorcery to add its ability.)
Landfall — Whenever a land you control enters, you gain 1 life.
{2}{G}: Level 2
You may play an additional land on each of your turns.
{4}{G}: Level 3
When this Class becomes level 3, target land you control becomes a creature with haste and "This creature's power and toughness are each equal to the number of lands you control." It's still a land.