Might of the Masses

Target creature gets +1/+1 until end of turn for each creature you control.

Halo Hopper

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Sprout Swarm

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Create a 1/1 green Saproling creature token.

Relic of Progenitus

{T}: Target player exiles a card from their graveyard.
{1}, Exile Relic of Progenitus: Exile all graveyards. Draw a card.

Night Soil

{1}, Exile two creature cards from a single graveyard: Create a 1/1 green Saproling creature token.

Ceremonial Knife

Equipped creature gets +1/+0 and has "Whenever this creature deals combat damage, create a Blood token." (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Generous Ent

Reach
When Generous Ent enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Forestcycling {1} ({1}, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

Jewel Thief

Vigilance, trample
When Jewel Thief enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Glimmer Bairn

Sacrifice a token: Glimmer Bairn gets +2/+2 until end of turn.

Gleeful Sabotage

Destroy target artifact or enchantment.
Conspire (As you cast this spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose a new target for the copy.)

Scatter the Seeds

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Create three 1/1 green Saproling creature tokens.

Prizefight

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)
Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Khalni Garden

Khalni Garden enters tapped.
When Khalni Garden enters, create a 0/1 green Plant creature token.
{T}: Add {G}.

Chatter of the Squirrel

Create a 1/1 green Squirrel creature token.
Flashback {1}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Forest

Nest Invader

When Nest Invader enters, create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Cloakwood Swarmkeeper

Gathered Swarm — Whenever one or more tokens you control enter, put a +1/+1 counter on Cloakwood Swarmkeeper.

Deglamer

Choose target artifact or enchantment. Its owner shuffles it into their library.

Essence Warden

Whenever another creature enters, you gain 1 life.

Fists of Ironwood

Enchant creature
When Fists of Ironwood enters, create two 1/1 green Saproling creature tokens.
Enchanted creature has trample.