Have

Blight Sickle

Equipped creature gets +1/+0 and has wither. (It deals damage to creatures in the form of -1/-1 counters.)
Equip {2}

Fellwar Stone

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

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Infectious Inquiry

You draw two cards and you lose 2 life. Each opponent gets a poison counter.

Subtle Strike

Choose one or both —
• Target creature gets -1/-1 until end of turn.
• Put a +1/+1 counter on target creature.

Splendid Agony

Distribute two -1/-1 counters among one or two target creatures.

Kulrath Knight

Flying
Wither (This deals damage to creatures in the form of -1/-1 counters.)
Creatures your opponents control with counters on them can't attack or block.

Rakdos Cluestone

{T}: Add {B} or {R}.
{B}{R}, {T}, Sacrifice this artifact: Draw a card.

Don't Have

Cannibalize

Choose two target creatures controlled by the same player. Exile one of those creatures and put two +1/+1 counters on the other.

Smelt

Spread the Sickness

Destroy target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Contagious Nim

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Grim Affliction

Put a -1/-1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Phyrexian Digester

Smoldering Spires

This land enters tapped.
When this land enters, target creature can't block this turn.
{T}: Add {R}.

Tainted Strike

Target creature gets +1/+0 and gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Blur of Blades

Put a -1/-1 counter on target creature. Blur of Blades deals 2 damage to that creature's controller.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Doom Blade

Ashnod's Altar

Fang Skulkin

{2}: Target black creature gains wither until end of turn. (It deals damage to creatures in the form of -1/-1 counters.)

Ichorclaw Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this creature becomes blocked, it gets +2/+2 until end of turn.

Fume Spitter

Sacrifice this creature: Put a -1/-1 counter on target creature.

Pith Driller

({B/P} can be paid with either {B} or 2 life.)
When this creature enters, put a -1/-1 counter on target creature.

Flensermite

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Myr Scrapling

Sacrifice this creature: Put a +1/+1 counter on target creature.

Heightened Reflexes

Target creature gets +1/+0 until end of turn. Put a first strike counter on it.

Rakdos Signet

Festering Mummy

When this creature dies, you may put a -1/-1 counter on target creature.

Cultbrand Cinder

When this creature enters, put a -1/-1 counter on target creature.

Virulent Wound

Put a -1/-1 counter on target creature. When that creature dies this turn, its controller gets a poison counter.

Seething Song

Swamp

Command Tower

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

Cinderbones

Wither (This deals damage to creatures in the form of -1/-1 counters.)
{1}{B}: Regenerate this creature.

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Armor Thrull

{T}, Sacrifice this creature: Put a +1/+2 counter on target creature.

Lesser Werewolf

{B}: If this creature's power is 1 or more, it gets -1/-0 until end of turn and put a -0/-1 counter on target creature blocking or blocked by this creature. Activate only during the declare blockers step.

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Shattering Pulse

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.)
Destroy target artifact.

Ogre Menial

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{R}: This creature gets +1/+0 until end of turn.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Vector Asp

{B}: This creature gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Razor Swine

First strike
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Terminate

Destroy target creature. It can't be regenerated.

Plague Stinger

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Ashnod's Transmogrant

{T}, Sacrifice this artifact: Put a +1/+1 counter on target nonartifact creature. That creature becomes an artifact in addition to its other types.

Dark Ritual

Puncture Bolt

Puncture Bolt deals 1 damage to target creature. Put a -1/-1 counter on that creature.

Instill Infection

Put a -1/-1 counter on target creature.
Draw a card.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Sickle Ripper

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Volt Charge

Volt Charge deals 3 damage to any target. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Inescapable Brute

Wither (This deals damage to creatures in the form of -1/-1 counters.)
This creature must be blocked if able.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Eternal Thirst

Enchant creature
Enchanted creature has lifelink and "Whenever a creature an opponent controls dies, put a +1/+1 counter on this creature." (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Torture

Enchant creature
{1}{B}: Put a -1/-1 counter on enchanted creature.

Unexpected Fangs

Put a +1/+1 counter and a lifelink counter on target creature.

Pyretic Ritual

Corpse Cur

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When this creature enters, you may return target creature card with infect from your graveyard to your hand.

Scar

Mountain

Phyresis

Enchant creature
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Professor's Warning

Choose one —
• Put a +1/+1 counter on target creature.
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Rustrazor Butcher

First strike
Wither (This deals damage to creatures in the form of -1/-1 counters.)

Brighthearth Banneret

Elemental spells and Warrior spells you cast cost {1} less to cast.
Reinforce 1—{1}{R} ({1}{R}, Discard this card: Put a +1/+1 counter on target creature.)

Serrated Arrows

This artifact enters with three arrowhead counters on it.
At the beginning of your upkeep, if there are no arrowhead counters on this artifact, sacrifice it.
{T}, Remove an arrowhead counter from this artifact: Put a -1/-1 counter on target creature.

Explosive Entry

Destroy up to one target artifact. Put a +1/+1 counter on up to one target creature.

Sign in Blood

Target player draws two cards and loses 2 life.

Night's Whisper

Blackcleave Goblin

Haste
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)