Lantern of Insight

Players play with the top card of their libraries revealed.
{T}, Sacrifice Lantern of Insight: Target player shuffles.

Mistvein Borderpost

You may pay {1} and return a basic land you control to its owner's hand rather than pay this spell's mana cost.
Mistvein Borderpost enters the battlefield tapped.
{T}: Add {U} or {B}.

Command Tower

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

Ghoulcaller's Bell

Castle Vantress

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

Wizened Snitches

Flying
Players play with the top card of their libraries revealed.

Baleful Strix

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

Circu, Dimir Lobotomist

Whenever you cast a blue spell, exile the top card of target player's library.
Whenever you cast a black spell, exile the top card of target player's library.
Your opponents can't cast spells with the same name as a card exiled with Circu, Dimir Lobotomist.

Drowned Catacomb

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

Fetid Pools

({T}: Add {U} or {B}.)
Fetid Pools enters the battlefield tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Umbris, Fear Manifest

Umbris, Fear Manifest gets +1/+1 for each card your opponents own in exile.
Whenever Umbris or another Nightmare or Horror enters the battlefield under your control, target opponent exiles cards from the top of their library until they exile a land card.

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters the battlefield tapped unless you control three or more other Islands.
When Mystic Sanctuary enters the battlefield untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Foreshadow

Choose a card name, then target opponent mills a card. If a card with the chosen name was milled this way, you draw a card.
Draw a card at the beginning of the next turn's upkeep.

Sunken Hollow

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

Academy Ruins

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

Swamp

Trinket Mage

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.

Ashiok, Nightmare Weaver

+2: Exile the top three cards of target opponent's library.
−X: Put a creature card with mana value X exiled with Ashiok, Nightmare Weaver onto the battlefield under your control. That creature is a Nightmare in addition to its other types.
−10: Exile all cards from all opponents' hands and graveyards.

Pyxis of Pandemonium

{T}: Each player exiles the top card of their library face down.
{7}, {T}, Sacrifice Pyxis of Pandemonium: Each player turns face up all cards they own exiled with Pyxis of Pandemonium, then puts all permanent cards among them onto the battlefield.

Vampiric Tutor

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

Moonring Island

({T}: Add {U}.)
Moonring Island enters the battlefield tapped.
{U}, {T}: Look at the top card of target player's library. Activate only if you control two or more blue permanents.

Dimir Aqueduct

Dimir Aqueduct enters the battlefield tapped.
When Dimir Aqueduct enters the battlefield, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Codex Shredder

{T}: Target player mills a card. (They put the top card of their library into their graveyard.)
{5}, {T}, Sacrifice Codex Shredder: Return target card from your graveyard to your hand.

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.

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Thought Scour

Target player mills two cards.
Draw a card.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Bojuka Bog

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

Predict

Choose a card name, then target player mills a card. If a card with the chosen name was milled this way, you draw two cards. Otherwise, you draw a card.

The Mycosynth Gardens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{X}, {T}: The Mycosynth Gardens becomes a copy of target nontoken artifact you control with mana value X.

Island

Creeping Tar Pit

Creeping Tar Pit enters the battlefield tapped.
{T}: Add {U} or {B}.
{1}{U}{B}: Creeping Tar Pit becomes a 3/2 blue and black Elemental creature until end of turn and can't be blocked this turn. It's still a land.

Shipwreck Marsh

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

Urza's Saga

(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.

Urborg, Tomb of Yawgmoth

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

Morphic Pool

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

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Castle Locthwain

Castle Locthwain enters the battlefield tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.