Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Getting

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Cabal Coffers

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

Have

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Dauthi Voidwalker

Shadow (This creature can block or be blocked by only creatures with shadow.)
If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it.
{T}, Sacrifice Dauthi Voidwalker: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Rust Elemental

Flying
At the beginning of your upkeep, sacrifice an artifact other than Rust Elemental. If you can't, tap Rust Elemental and you lose 4 life.

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Sleeper Agent

When Sleeper Agent enters the battlefield, target opponent gains control of it.
At the beginning of your upkeep, Sleeper Agent deals 2 damage to you.

Master of the Feast

Flying
At the beginning of your upkeep, each opponent draws a card.

Plague Reaver

At the beginning of your end step, sacrifice each other creature you control.
Discard two cards, Sacrifice Plague Reaver: Choose target opponent. Return Plague Reaver to the battlefield under that player's control at the beginning of their next upkeep.

Darkwater Catacombs

Fellwar Stone

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

Jet Medallion

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

Rite of Belzenlok

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Create two 0/1 black Cleric creature tokens.
III — Create a 6/6 black Demon creature token with flying, trample, and "At the beginning of your upkeep, sacrifice another creature. If you can't, this creature deals 6 damage to you."

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Sol Ring

Animate Dead

Enchant creature card in a graveyard
When Animate Dead enters the battlefield, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Greater Harvester

At the beginning of your upkeep, sacrifice a permanent.
Whenever Greater Harvester deals combat damage to a player, that player sacrifices two permanents.

Exotic Orchard

Reliquary Tower

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

Donate

Target player gains control of target permanent you control.

Takenuma, Abandoned Mire

{T}: Add {B}.
Channel — {3}{B}, Discard Takenuma, Abandoned Mire: Mill three cards, then return a creature or planeswalker card from your graveyard to your hand. This ability costs {1} less to activate for each legendary creature you control.

Counterspell

Ebonblade Reaper

Whenever Ebonblade Reaper attacks, you lose half your life, rounded up.
Whenever Ebonblade Reaper deals combat damage to a player, that player loses half their life, rounded up.
Morph {3}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Castle Vantress

Castle Vantress enters the battlefield tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

Grinning Demon

At the beginning of your upkeep, you lose 2 life.
Morph {2}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Dimir Signet

Spark Double

You may have Spark Double enter the battlefield as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Island

Drowned Catacomb

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Ebon Drake

Flying
Whenever a player casts a spell, you lose 1 life.

Demonic Taskmaster

Flying
At the beginning of your upkeep, sacrifice a creature other than Demonic Taskmaster.

Corrupted Conscience

Enchant creature
You control enchanted 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.)

Reins of Power

Untap all creatures you control and all creatures target opponent controls. You and that opponent each gain control of all creatures the other controls until end of turn. Those creatures gain haste until end of turn.

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Curse of Disturbance

Enchant player
Whenever enchanted player is attacked, create a 2/2 black Zombie creature token. Each opponent attacking that player does the same.

Heartless Summoning

Creature spells you cast cost {2} less to cast.
Creatures you control get -1/-1.

Taniwha

Trample
Phasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)
At the beginning of your upkeep, all lands you control phase out. (They phase in before you untap during your next untap step.)

Thought Vessel

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

Vow of Flight

Enchant creature
Enchanted creature gets +2/+2, has flying, and can't attack you or planeswalkers you control.

Steel Golem

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.

Apprentice Necromancer

{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.

Persist

Return target nonlegendary creature card from your graveyard to the battlefield with a -1/-1 counter on it.

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters the battlefield tapped unless you control two or more basic lands.

Sakashima of a Thousand Faces

You may have Sakashima of a Thousand Faces enter the battlefield as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Swamp

Command Tower

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

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Shipwreck Marsh

Shipwreck Marsh enters the battlefield tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Sly Instigator

{U}, {T}: Until your next turn, target creature an opponent controls can't be blocked. Goad that creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Desecration Elemental

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever a player casts a spell, sacrifice a creature.

Wretched Anurid

Whenever another creature enters the battlefield, you lose 1 life.

Alexi's Cloak

Flash
Enchant creature
Enchanted creature has shroud. (It can't be the target of spells or abilities.)

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Phyrexian Vatmother

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
At the beginning of your upkeep, you get a poison counter.

Gisa, Glorious Resurrector

If a creature an opponent controls would die, exile it instead.
At the beginning of your upkeep, put all creature cards exiled with Gisa, Glorious Resurrector onto the battlefield under your control. They gain decayed. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Hellcarver Demon

Flying
Whenever Hellcarver Demon deals combat damage to a player, sacrifice all other permanents you control and discard your hand. Exile the top six cards of your library. You may cast any number of spells from among cards exiled this way without paying their mana costs.

Ledger Shredder

Flying
Whenever a player casts their second spell each turn, Ledger Shredder connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Baleful Strix

Flying, deathtouch
When Baleful Strix enters the battlefield, draw a card.

Grid Monitor

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Phage the Untouchable

When Phage the Untouchable enters the battlefield, if you didn't cast it from your hand, you lose the game.
Whenever Phage deals combat damage to a creature, destroy that creature. It can't be regenerated.
Whenever Phage deals combat damage to a player, that player loses the game.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Clever Impersonator

You may have Clever Impersonator enter the battlefield as a copy of any nonland permanent on the battlefield.

Homeward Path

{T}: Add {C}.
{T}: Each player gains control of all creatures they own.

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Legerdemain

Exchange control of target artifact or creature and another target permanent that shares one of those types with it. (This effect lasts indefinitely.)

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Drinker of Sorrow

Drinker of Sorrow can't block.
Whenever Drinker of Sorrow deals combat damage, sacrifice a permanent.

Phyrexian Soulgorger

Cumulative upkeep—Sacrifice a creature. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Rotting Regisaur

At the beginning of your upkeep, discard a card.

Sudden Substitution

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Exchange control of target noncreature spell and target creature. Then the spell's controller may choose new targets for it.

Flesh Reaver

Whenever Flesh Reaver deals damage to a creature or opponent, Flesh Reaver deals that much damage to you.

Morphic Pool

Morphic Pool enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have Phyrexian Metamorph enter the battlefield as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Choked Estuary

As Choked Estuary enters the battlefield, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters the battlefield tapped.
{T}: Add {U} or {B}.

Thought Eater

Flying
Your maximum hand size is reduced by three.

Dissipation Field

Whenever a permanent deals damage to you, return it to its owner's hand.

Arcane Signet

Karn's Bastion

{T}: Add {C}.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)