Keeper of Secrets

First strike, haste
Symphony of Pain — Whenever you cast a spell from anywhere other than your hand, Keeper of Secrets deals damage equal to that spell's mana value to target opponent.

Blood Seeker

Whenever a creature an opponent controls enters, you may have that player lose 1 life.

Sardian Avenger

First strike, trample
Whenever Sardian Avenger attacks, it gets +X/+0 until end of turn, where X is the number of artifacts your opponents control.
Whenever an artifact an opponent controls is put into a graveyard from the battlefield, Sardian Avenger deals 1 damage to that player.

Fate Unraveler

Whenever an opponent draws a card, Fate Unraveler deals 1 damage to that player.

Ob Nixilis, Captive Kingpin

Flying, trample
Whenever one or more opponents each lose exactly 1 life, put a +1/+1 counter on Ob Nixilis, Captive Kingpin. Exile the top card of your library. Until your next end step, you may play that card.

Aurora of Emrakul

Flying, deathtouch
Whenever Aurora of Emrakul attacks, each opponent loses 3 life.

Cryptolith Fragment

Cryptolith Fragment enters tapped.
{T}: Add one mana of any color. Each player loses 1 life.
At the beginning of your upkeep, if each player has 10 or less life, transform Cryptolith Fragment.

Cryptolith Fragment // Aurora of Emrakul

Spiteful Prankster

During your turn, Spiteful Prankster has first strike.
Whenever another creature dies, Spiteful Prankster deals 1 damage to target player or planeswalker.

Vicious Rumors

Vicious Rumors deals 1 damage to each opponent. Each opponent discards a card, then mills a card. You gain 1 life.

Forsaken Wastes

Players can't gain life.
At the beginning of each player's upkeep, that player loses 1 life.
Whenever Forsaken Wastes becomes the target of a spell, that spell's controller loses 5 life.

Nadier's Nightblade

Whenever a token you control leaves the battlefield, each opponent loses 1 life and you gain 1 life.

Blood Moon

Aether Sting

Whenever an opponent casts a creature spell, Aether Sting deals 1 damage to that player.

Burning Earth

Whenever a player taps a nonbasic land for mana, Burning Earth deals 1 damage to that player.

Liability

Whenever a nontoken permanent is put into a player's graveyard from the battlefield, that player loses 1 life.

Trespasser's Curse

Enchant player
Whenever a creature enchanted player controls enters, that player loses 1 life and you gain 1 life.

Mage Hunter

Whenever an opponent casts or copies an instant or sorcery spell, they lose 1 life.

Tunneling Geopede

Landfall — Whenever a land you control enters, Tunneling Geopede deals 1 damage to each opponent.

Baeloth Barrityl, Entertainer

Creatures your opponents control with power less than Baeloth Barrityl's power are goaded. (They attack each combat if able and attack a player other than you if able.)
Whenever a goaded attacking or blocking creature dies, you create a Treasure token.
Choose a Background (You can have a Background as a second commander.)

Prosper, Tome-Bound

Deathtouch
Mystic Arcanum — At the beginning of your end step, exile the top card of your library. Until the end of your next turn, you may play that card.
Pact Boon — Whenever you play a card from exile, create a Treasure token.

Vengeful Ancestor

Flying
Whenever Vengeful Ancestor enters or attacks, goad target creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Whenever a goaded creature attacks, it deals 1 damage to its controller.

Check for Traps

Target opponent reveals their hand. You choose a nonland card from it. Exile that card. If an instant card or a card with flash is exiled this way, they lose 1 life. Otherwise, you lose 1 life.

Mardu Shadowspear

Whenever Mardu Shadowspear attacks, each opponent loses 1 life.
Dash {1}{B} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Smolder Initiate

Whenever a player casts a black spell, you may pay {1}. If you do, target player loses 1 life.

Mayhem Devil

Whenever a player sacrifices a permanent, Mayhem Devil deals 1 damage to any target.

Blood Reckoning

Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life.

Pain Distributor

Menace
Whenever a player casts their first spell each turn, they create a Treasure token.
Whenever an artifact an opponent controls is put into a graveyard from the battlefield, Pain Distributor deals 1 damage to that player.

Karazikar, the Eye Tyrant

Whenever you attack a player, tap target creature that player controls and goad it. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Whenever an opponent attacks another one of your opponents, you and the attacking player each draw a card and lose 1 life.

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Mind Rake

Target player discards two cards.
Overload {1}{B} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Valakut Exploration

Landfall — Whenever a land you control enters, exile the top card of your library. You may play that card for as long as it remains exiled.
At the beginning of your end step, if there are cards exiled with Valakut Exploration, put them into their owner's graveyard, then Valakut Exploration deals that much damage to each opponent.

Kederekt Parasite

Whenever an opponent draws a card, if you control a red permanent, you may have Kederekt Parasite deal 1 damage to that player.

Hissing Iguanar

Whenever another creature dies, you may have Hissing Iguanar deal 1 damage to target player or planeswalker.

Roiling Vortex

At the beginning of each player's upkeep, Roiling Vortex deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, Roiling Vortex deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.

Retreat to Hagra

Landfall — Whenever a land you control enters, choose one —
• Target creature gets +1/+0 and gains deathtouch until end of turn.
• Each opponent loses 1 life and you gain 1 life.

Hissing Miasma

Whenever a creature attacks you, its controller loses 1 life.

Spear Spewer

Defender
{T}: Spear Spewer deals 1 damage to each player.

Oppression

Whenever a player casts a spell, that player discards a card.

Goblin Fireslinger

{T}: Goblin Fireslinger deals 1 damage to target player or planeswalker.

Sire of Insanity

At the beginning of each end step, each player discards their hand.

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Soot Imp

Flying
Whenever a player casts a nonblack spell, that player loses 1 life.

Stranglehold

Your opponents can't search libraries.
If an opponent would begin an extra turn, that player skips that turn instead.

Mind Swords

If you control a Swamp, you may sacrifice a creature rather than pay this spell's mana cost.
Each player exiles two cards from their hand.

Flame Jab

Flame Jab deals 1 damage to any target.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Disciple of the Vault

Whenever an artifact is put into a graveyard from the battlefield, you may have target opponent lose 1 life.

Immolation Shaman

Whenever an opponent activates an ability of an artifact, creature, or land that isn't a mana ability, Immolation Shaman deals 1 damage to that player.
{3}{R}{R}: Immolation Shaman gets +3/+3 and gains menace until end of turn.

Battle Strain

Whenever a creature blocks, Battle Strain deals 1 damage to that creature's controller.

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, Rampaging Ferocidon deals 1 damage to that creature's controller.

Kardur, Doomscourge

When Kardur, Doomscourge enters, until your next turn, creatures your opponents control attack each combat if able and attack a player other than you if able.
Whenever an attacking creature dies, each opponent loses 1 life and you gain 1 life.