Flooded Woodlands

Green creatures can't attack unless their controller sacrifices a land of their choice for each green creature they control that's attacking. (This cost is paid as attackers are declared.)

Sword of Feast and Famine

Equipped creature gets +2/+2 and has protection from black and from green.
Whenever equipped creature deals combat damage to a player, that player discards a card and you untap all lands you control.
Equip {2}

Deathmark

Darkslick Shores

Darkslick Shores enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Change the Equation

Choose one —
• Counter target spell with mana value 2 or less.
• Counter target red or green spell with mana value 6 or less.

Painter's Servant

As Painter's Servant enters, choose a color.
All cards that aren't on the battlefield, spells, and permanents are the chosen color in addition to their other colors.

Leshrac's Sigil

Whenever an opponent casts a green spell, you may pay {B}{B}. If you do, look at that player's hand and choose a card from it. The player discards that card.
{B}{B}: Return Leshrac's Sigil to its owner's hand.

Deathgrip

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Scuttlemutt

{T}: Add one mana of any color.
{T}: Target creature becomes the color or colors of your choice until end of turn.

Dunerider Outlaw

Protection from green
At the beginning of each end step, if Dunerider Outlaw dealt damage to an opponent this turn, put a +1/+1 counter on it.

Swamp

Island

Shifting Sky

As Shifting Sky enters, choose a color.
All nonland permanents are the chosen color.

Bereavement

Whenever a green creature dies, its controller discards a card.

Eastern Paladin

{B}{B}, {T}: Destroy target green creature.

Peat Bog

Peat Bog enters tapped with two depletion counters on it.
{T}, Remove a depletion counter from Peat Bog: Add {B}{B}. If there are no depletion counters on Peat Bog, sacrifice it.