Golgari Signet

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Grim Backwoods

{T}: Add {C}.
{2}{B}{G}, {T}, Sacrifice a creature: Draw a card.

Coldsteel Heart

Coldsteel Heart enters tapped.
As Coldsteel Heart enters, choose a color.
{T}: Add one mana of the chosen color.

Rishkar's Expertise

Draw cards equal to the greatest power among creatures you control.
You may cast a spell with mana value 5 or less from your hand without paying its mana cost.

Forest

Foul Orchard

Foul Orchard enters tapped.
{T}: Add {B} or {G}.

Tangle Asp

Whenever Tangle Asp blocks or becomes blocked by a creature, destroy that creature at end of combat.

Golgari Guildgate

Golgari Guildgate enters tapped.
{T}: Add {B} or {G}.

Swamp

Mirkwood Spider

Deathtouch
Whenever Mirkwood Spider attacks, target legendary creature you control gains deathtouch until end of turn.

Rendmaw, Creaking Nest

Menace, reach
When Rendmaw, Creaking Nest enters and whenever you play a card with two or more card types, each player creates a tapped 2/2 black Bird creature token with flying. The tokens are goaded for the rest of the game. (They attack each combat if able and attack a player other than you if able.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Bladebrand

Target creature gains deathtouch until end of turn.
Draw a card.

Endless Obedience

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.)
Put target creature card from a graveyard onto the battlefield under your control.

Tree of Tales

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Horn of the Mark

Whenever two or more creatures you control attack a player, look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Golgari Rot Farm

Golgari Rot Farm enters tapped.
When Golgari Rot Farm enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.

Weathered Sentinels

Defender, vigilance, reach, trample
Weathered Sentinels can attack players who attacked you during their last turn as though it didn't have defender.
Whenever Weathered Sentinels attacks, it gets +3/+3 and gains indestructible until end of turn.

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Acidic Slime enters, destroy target artifact, enchantment, or land.

Nettlecyst

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1 for each artifact and/or enchantment you control.
Equip {2}

Jungle Hollow

Jungle Hollow enters tapped.
When Jungle Hollow enters, you gain 1 life.
{T}: Add {B} or {G}.