When Abyssal Gatekeeper dies, each player sacrifices a creature.

Return from your graveyard to the battlefield any number of target creature cards that each have a different mana value X or less.

As Agadeem, the Undercrypt enters the battlefield, you may pay 3 life. If you don't, it enters the battlefield tapped.

{T}: Add {B}.

You may spend mana as though it were mana of any color to activate abilities of creatures you control.

Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.

{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.

As an additional cost to cast this spell, pay {4} or sacrifice an artifact or creature.

Destroy target creature or planeswalker.

{B}, {T}, Sacrifice Apprentice Necromancer: Return target creature card from your graveyard to the battlefield. That creature gains haste. At the beginning of the next end step, sacrifice it.

Trample

Whenever another artifact enters the battlefield, put a +1/+1 counter on Arcbound Crusher.

Modular 1 (This creature enters the battlefield with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

At the beginning of your upkeep, you may move a +1/+1 counter from target creature onto Arcbound Fiend.

Modular 3 (This creature enters the battlefield with three +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Sacrifice an artifact: Put a +1/+1 counter on Arcbound Ravager.

Modular 1 (This creature enters the battlefield with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Remove a +1/+1 counter from Arcbound Reclaimer: Put target artifact card from your graveyard on top of your library.

Modular 2 (This creature enters the battlefield with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Whenever Arcbound Slith deals combat damage to a player, put a +1/+1 counter on it.

Modular 1 (This creature enters the battlefield with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Flying

Modular 1 (This creature enters the battlefield with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Modular 1 (This creature enters the battlefield with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Sacrifice a creature: Add {C}{C}.

When Bastion of Remembrance enters the battlefield, create a 1/1 white Human Soldier creature token.

Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.

When Big Game Hunter enters the battlefield, destroy target creature with power 4 or greater. It can't be regenerated.

Madness {B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Whenever a creature dies, put a charge counter on Black Market.

At the beginning of your precombat main phase, add {B} for each charge counter on Black Market.

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

Whenever a creature enters the battlefield under an opponent's control, you may have that player lose 1 life.

Sacrifice a creature: Put a +1/+1 counter on Bloodflow Connoisseur.

Bojuka Bog enters the battlefield tapped.

When Bojuka Bog enters the battlefield, exile target player's graveyard.

{T}: Add {B}.

Flying

Echo {2}{B} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)

When Bone Shredder enters the battlefield, destroy target nonartifact, nonblack creature.

Black creature spells you cast cost {1} less to cast.

Whenever you cast a creature spell, each opponent loses 1 life and you gain 1 life.

When Burglar Rat enters the battlefield, each opponent discards a card.

{2}, {T}: Add {B} for each Swamp you control.

{T}: Add {C}.

{3}, {T}: Add {B} for each basic Swamp you control.

Flying

When Cadaver Imp enters the battlefield, you may return target creature card from your graveyard to your hand.

Carrion Feeder can't block.

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

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.

Equip commander {3}

Equip {5}

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Whenever you tap a Swamp for mana, add an additional {B}.

{T}, Sacrifice a creature: Put a charge counter on Culling Dais.

{1}, Sacrifice Culling Dais: Draw a card for each charge counter on Culling Dais.

As an additional cost to cast this spell, sacrifice a creature.

Add {B}{B}{B}{B}.

Destroy all creatures. They can't be regenerated.

Add {B}{B}{B}.

Whenever another creature dies, you may gain 1 life.

Whenever one or more creature cards leave your graveyard, create a 1/1 black Bat creature token with flying.

Flash

Whenever a creature you control dies, each opponent sacrifices a creature.

{3}, {T}: Double the amount of each type of unspent mana you have.

As an additional cost to cast this spell, sacrifice a creature or pay {3}{B}.

Exile target creature or planeswalker.

When Elderfang Disciple enters the battlefield, each opponent discards a card.

{2}, {T}, Sacrifice Expedition Map: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Sacrifice a creature: Destroy target artifact. Activate only during your upkeep and only once each turn.

Whenever a creature you control dies, each other player sacrifices a creature.

When Greedy Freebooter dies, scry 1 and create a Treasure token. (To scry 1, look at the top card of your library. You may put that card on the bottom. A Treasure token is an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

{T}: Add {C}.

{T}, Sacrifice a creature: You gain 1 life.

Iron Apprentice enters the battlefield with a +1/+1 counter on it.

When Iron Apprentice dies, if it had counters on it, put those counters on target creature you control.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)

Equip {0}

Whenever you cast an artifact creature spell, it gains sunburst. (It enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it.)

At the beginning of your end step, if there are thirty or more counters among artifacts and creatures you control, Lux Artillery deals 10 damage to each opponent.

Flash

Indestructible

When Mithril Coat enters the battlefield, attach it to target legendary creature you control.

Equipped creature has indestructible.

Equip {3}

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

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

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

Enchant creature

Enchanted creature has "Whenever another creature dies, put a +1/+1 counter on this creature."

When enchanted creature dies, look at the top X cards of your library, where X is its power. Put one of those cards into your hand and the rest on the bottom of your library in a random order.

When Nezumi Informant enters the battlefield, each opponent discards a card.

{T}: Add {C}.

{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Whenever a nontoken creature you control dies, create a 2/2 black Zombie creature token.

When Perilous Myr dies, it deals 2 damage to any target.

{T}: Add {C}.

{T}, Sacrifice a creature: Add {B}{B}.

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.")

{2}, {T}, Sacrifice a creature: Search your library for a creature card that shares a creature type with the sacrificed creature and has mana value equal to 1 plus that creature's mana value. Put that card onto the battlefield, then shuffle. Activate only as a sorcery.

You have no maximum hand size.

{T}: Add {C}.

Modular 2 (This creature enters the battlefield with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

{T}, Sacrifice an artifact: Search your library for a Construct card, reveal it, put it into your hand, then shuffle.

When Serrated Scorpion dies, it deals 2 damage to each opponent and you gain 2 life.

Whenever a creature dies, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

{4}{B}: Each opponent loses 2 life and you gain 2 life. Activate only if there are four or more creature cards in your graveyard.

Whenever a creature with power 1 or less is put into your graveyard from the battlefield, you may return that card to the battlefield at the beginning of the next end step if Shirei, Shizo's Caretaker is still on the battlefield.

When Skittering Surveyor enters the battlefield, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Equipped creature gets +1/-1.

Whenever equipped creature dies, draw two cards.

Equip {1}

Flying

When Skyscanner enters the battlefield, draw a card.

{T}, Sacrifice a black or artifact creature: Add an amount of {B} equal to the sacrificed creature's mana value.

Add {B} for each creature card in your graveyard.

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

When Tattered Mummy dies, each opponent loses 2 life.

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.

At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Each land is a Swamp in addition to its other land types.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)

I -- Urza's Saga gains "{T}: Add {C}."

II -- Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"

III -- Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

{1}{B}, Sacrifice a creature: You gain 1 life and draw a card.

As an additional cost to cast this spell, sacrifice a creature.

Draw two cards.

When Virus Beetle enters the battlefield, each opponent discards a card.

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Whenever an opponent discards a creature card, create a 2/2 black Zombie creature token.

Whenever an opponent discards a land card, add {B}{B}.

Whenever an opponent discards a noncreature, nonland card, draw a card.

When Yarok's Fenlurker enters the battlefield, each opponent exiles a card from their hand.

{2}{B}: Yarok's Fenlurker gets +1/+1 until end of turn.

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