Bhaal, Lord of Murder

As long as your life total is less than or equal to half your starting life total, Bhaal, Lord of Murder has indestructible.
Whenever another nontoken creature you control dies, put a +1/+1 counter on target creature and goad it.

Bloodthirsty Blade

Equipped creature gets +2/+0 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
{1}: Attach Bloodthirsty Blade to target creature an opponent controls. Activate only as a sorcery.

A Killer Among Us

When A Killer Among Us enters the battlefield, create a 1/1 white Human creature token, a 1/1 blue Merfolk creature token, and a 1/1 red Goblin creature token. Then secretly choose Human, Merfolk, or Goblin.
Sacrifice A Killer Among Us, Reveal the creature type you chose: If target attacking creature token is the chosen type, put three +1/+1 counters on it and it gains deathtouch until end of turn.

Curse of Chaos

Enchant player
Whenever a player attacks enchanted player with one or more creatures, that attacking player may discard a card. If the player does, they draw a card.

Silumgar Assassin

Creatures with power greater than Silumgar Assassin's power can't block it.
Megamorph {2}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Silumgar Assassin is turned face up, destroy target creature with power 3 or less an opponent controls.

Disrupt Decorum

Goad all creatures you don't control. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Vow of Malice

Enchant creature
Enchanted creature gets +2/+2, has intimidate, and can't attack you or planeswalkers you control. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Predatory Impetus

Enchant creature
Enchanted creature gets +3/+3, must be blocked if able, and is goaded. (It attacks each combat if able and attacks a player other than you if able.)

Gut, True Soul Zealot

Whenever you attack, you may sacrifice another creature or an artifact. If you do, create a 4/1 black Skeleton creature token with menace that's tapped and attacking. (It can't be blocked except by two or more creatures.)
Choose a Background (You can have a Background as a second commander.)

Witch Hunt

Players can't gain life.
At the beginning of your upkeep, Witch Hunt deals 4 damage to you.
At the beginning of your end step, target opponent chosen at random gains control of Witch Hunt.

Parasitic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, its controller loses 2 life and you gain 2 life.

Mari, the Killing Quill

Whenever a creature an opponent controls dies, exile it with a hit counter on it.
Assassins, Mercenaries, and Rogues you control have deathtouch and "Whenever this creature deals combat damage to a player, you may remove a hit counter from a card that player owns in exile. If you do, draw a card and create two Treasure tokens."

Curse of Stalked Prey

Enchant player
Whenever a creature deals combat damage to enchanted player, put a +1/+1 counter on that creature.

Murderous Cut

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Destroy target creature.

Curse of Vengeance

Enchant player
Whenever enchanted player casts a spell, put a spite counter on Curse of Vengeance.
When enchanted player loses the game, you gain X life and draw X cards, where X is the number of spite counters on Curse of Vengeance.

Skin Shedder

Skin Invasion

Enchant creature
Enchanted creature attacks each combat if able.
When enchanted creature dies, return Skin Invasion to the battlefield transformed under your control.

Skin Invasion // Skin Shedder

Curse of Predation

Enchant player
Whenever a creature attacks enchanted player, put a +1/+1 counter on it.

Shifting Shadow

Enchant creature
Enchanted creature has haste and "At the beginning of your upkeep, destroy this creature. Reveal cards from the top of your library until you reveal a creature card. Put that card onto the battlefield and attach Shifting Shadow to it, then put all other cards revealed this way on the bottom of your library in a random order."

Laurine, the Diversion

Partner with Kamber, the Plunderer (When this creature enters the battlefield, target player may put Kamber into their hand from their library, then shuffle.)
First strike
{2}, Sacrifice an artifact or creature: Goad target creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Sinister Waltz

Choose three target creature cards in your graveyard. Return two of them at random to the battlefield and put the other on the bottom of your library.

Xantcha, Sleeper Agent

Xantcha, Sleeper Agent enters the battlefield under the control of an opponent of your choice.
Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls.
{3}: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability.

Curse of the Nightly Hunt

Enchant player
Creatures enchanted player controls attack each combat if able.

Scarblade Elite

{T}, Exile an Assassin card from your graveyard: Destroy target creature.

Curse of Opulence

Enchant player
Whenever enchanted player is attacked, create a Gold token. Each opponent attacking that player does the same. (A Gold token is an artifact with "Sacrifice this artifact: Add one mana of any color.")

Murderous Redcap

When Murderous Redcap enters the battlefield, it deals damage equal to its power to any target.
Persist (When this creature 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.)

Grenzo, Havoc Raiser

Whenever a creature you control deals combat damage to a player, choose one —
• Goad target creature that player controls.
• Exile the top card of that player's library. Until end of turn, you may cast that card and you may spend mana as though it were mana of any color to cast that spell.

Kamber, the Plunderer

Partner with Laurine, the Diversion (When this creature enters the battlefield, target player may put Laurine into their hand from their library, then shuffle.)
Lifelink
Whenever a creature an opponent controls dies, you gain 1 life and create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

Curse of Bloodletting

Enchant player
If a source would deal damage to enchanted player, it deals double that damage to that player instead.