Tainted Wood

{T}: Add {C}.
{T}: Add {B} or {G}. Activate only if you control a Swamp.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Swamp

Golgari Rot Farm

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

Woodland Cemetery

This land enters tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Grist, the Hunger Tide

As long as Grist isn't on the battlefield, it's a 1/1 Insect creature in addition to its other types.
+1: Create a 1/1 black and green Insect creature token, then mill a card. If an Insect card was milled this way, put a loyalty counter on Grist and repeat this process.
−2: You may sacrifice a creature. When you do, destroy target creature or planeswalker.
−5: Each opponent loses life equal to the number of creature cards in your graveyard.

Overgrown Tomb

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

Witherbloom Command

Choose two —
• Target player mills three cards, then you return a land card from your graveyard to your hand.
• Destroy target noncreature, nonland permanent with mana value 2 or less.
• Target creature gets -3/-1 until end of turn.
• Target opponent loses 2 life and you gain 2 life.