Tourach's Chant

At the beginning of your upkeep, sacrifice Tourach's Chant unless you pay {B}.
Whenever a player puts a Forest onto the battlefield, Tourach's Chant deals 3 damage to that player unless they put a -1/-1 counter on a creature they control.

Tireless Tracker

Landfall — Whenever a land you control enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you sacrifice a Clue, put a +1/+1 counter on Tireless Tracker.

Nature's Wrath

At the beginning of your upkeep, sacrifice Nature's Wrath unless you pay {G}.
Whenever a player puts an Island or blue permanent onto the battlefield, that player sacrifices an Island or blue permanent.
Whenever a player puts a Swamp or black permanent onto the battlefield, that player sacrifices a Swamp or black permanent.

Stone-Seeder Hierophant

Landfall — Whenever a land you control enters, untap Stone-Seeder Hierophant.
{T}: Untap target land.

Exploration

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

Lifegift

Whenever a land enters, you may gain 1 life.

Polluted Bonds

Whenever a land an opponent controls enters, that player loses 2 life and you gain 2 life.

Krosan Grip

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Destroy target artifact or enchantment.

Lotus Cobra

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

Invader Parasite

Imprint — When Invader Parasite enters, exile target land.
Whenever a land an opponent controls with the same name as the exiled card enters, Invader Parasite deals 2 damage to that player.

Titania, Protector of Argoth

When Titania, Protector of Argoth enters, return target land card from your graveyard to the battlefield.
Whenever a land you control is put into a graveyard from the battlefield, create a 5/3 green Elemental creature token.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Zo-Zu the Punisher

Whenever a land enters, Zo-Zu the Punisher deals 2 damage to that land's controller.

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.

Thelon's Chant

At the beginning of your upkeep, sacrifice Thelon's Chant unless you pay {G}.
Whenever a player puts a Swamp onto the battlefield, Thelon's Chant deals 3 damage to that player unless the player puts a -1/-1 counter on a creature they control.

Tunnel Ignus

Whenever a land enters under an opponent's control, if that player had another land enter the battlefield under their control this turn, Tunnel Ignus deals 3 damage to that player.

Dingus Egg

Whenever a land is put into a graveyard from the battlefield, Dingus Egg deals 2 damage to that land's controller.

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.

Grazing Gladehart

Landfall — Whenever a land you control enters, you may gain 2 life.

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.

Ankh of Mishra

Whenever a land enters, Ankh of Mishra deals 2 damage to that land's controller.