{T}: Add {C}.

{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Whenever Ayara, First of Locthwain or another black creature enters the battlefield under your control, each opponent loses 1 life and you gain 1 life.

{T}, Sacrifice another black creature: Draw a card.

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

Horrors you control have menace.

Whenever a Horror you control deals combat damage to a player, that player mills that many cards.

At the beginning of your end step, choose target artifact or creature card in an opponent's graveyard that was put there from their library this turn. Put it onto the battlefield under your control.

Carrion Feeder can't block.

Sacrifice a creature: Put a +1/+1 counter on Carrion Feeder.

Consuming Aberration's power and toughness are each equal to the number of cards in your opponents' graveyards.

Whenever you cast a spell, each opponent reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.

When Dreadhound enters the battlefield, mill three cards. (Put the top three cards of your library into your graveyard.)

Whenever a creature dies or a creature card is put into a graveyard from a library, each opponent loses 1 life.

This spell costs {1} less to cast for each artifact you control.

When Emry, Lurker of the Loch enters the battlefield, mill four cards.

{T}: Choose target artifact card in your graveyard. You may cast that card this turn. (You still pay its costs. Timing rules still apply.)

Aberrant Tinkering -- When Grell Philosopher enters the battlefield and at the beginning of your upkeep, each Horror you control gains all activated abilities of target artifact an opponent controls until end of turn. You may spend blue mana as though it were mana of any color to activate those abilities.

Commander creatures you own have "Whenever this creature becomes tapped, it and other creatures you control that share a creature type with it each get +2/+0 and gain undying until end of turn." (When a creature with undying 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.)

When Manic Scribe enters the battlefield, each opponent mills three cards.

Delirium -- At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, that player mills three cards.

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.

{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

As an additional cost to cast this spell, sacrifice an artifact.

Search your library for an artifact card, put that card onto the battlefield, then shuffle.

When Tribute Mage enters the battlefield, you may search your library for an artifact card with mana value 2, reveal that card, put it into your hand, then shuffle.

When Trinket Mage enters the battlefield, you may search your library for an artifact card with mana value 1 or less, reveal that card, put it into your hand, then shuffle.

If a Zombie you control would deal combat damage to a player, instead that player mills that many cards.

Whenever a creature card is put into an opponent's graveyard from their library, exile that card and create a 2/2 black Zombie creature token.

Hive Mind -- Whenever a player mills one or more creature cards, you create a 1/1 black Horror creature token.

{1}, {T}: Target player mills three cards.

Choose a Background (You can have a Background as a second commander.)

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.