Desert

{T}: Add {C}.
{T}: Desert deals 1 damage to target attacking creature. Activate only during the end of combat step.

Swamp

Scuttlemutt

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

Retribution of the Ancients

{B}, Remove X +1/+1 counters from among creatures you control: Target creature gets -X/-X until end of turn.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Glaring Spotlight

Creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.
{3}, Sacrifice Glaring Spotlight: Creatures you control gain hexproof until end of turn and can't be blocked this turn.

Harvester of Souls

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever another nontoken creature dies, you may draw a card.

Leechridden Swamp

({T}: Add {B}.)
Leechridden Swamp enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Sol Ring

Mogis's Marauder

When Mogis's Marauder enters, up to X target creatures each gain intimidate and haste until end of turn, where X is your devotion to black. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it. Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Cauldron of Souls

{T}: Choose any number of target creatures. Each of those creatures gains persist until end of turn. (When it 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.)

Horobi, Death's Wail

Flying
Whenever a creature becomes the target of a spell or ability, destroy that creature.

Tetzimoc, Primal Death

Deathtouch
{B}, Reveal Tetzimoc, Primal Death from your hand: Put a prey counter on target creature. Activate only during your turn.
When Tetzimoc enters, destroy each creature your opponents control with a prey counter on it.

Scale of Chiss-Goria

Flash
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{T}: Target creature gets +0/+1 until end of turn.

Liquimetal Coating

{T}: Target permanent becomes an artifact in addition to its other types until end of turn.

Tooth of Chiss-Goria

Flash
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
{T}: Target creature gets +1/+0 until end of turn.

Touch of Darkness

One or more target creatures become black until end of turn.

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.