Grumgully, the Generous

Each other non-Human creature you control enters with an additional +1/+1 counter on it.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Forest

Putrid Goblin

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Goblin Bombardment

Sacrifice a creature: This enchantment deals 1 damage to any target.

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter with your choice of a +1/+1 counter or haste.)

Overgrown Tomb

({T}: Add {B} or {G}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Carrion Feeder

This creature can't block.
Sacrifice a creature: Put a +1/+1 counter on this creature.

Marsh Flats

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Blasting Station

{T}, Sacrifice a creature: This artifact deals 1 damage to any target.
Whenever a creature enters, you may untap this artifact.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Kitchen Finks

When this creature enters, you gain 2 life.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Lesser Masticore

As an additional cost to cast this spell, discard a card.
{4}: This creature deals 1 damage to target creature.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Swamp

Stomping Ground

({T}: Add {R} or {G}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.