Undercover Crocodelf

Whenever Undercover Crocodelf deals combat damage to a player, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Disguise {3}{G/U}{G/U} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Dimir Aqueduct

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

Relic of Progenitus

{T}: Target player exiles a card from their graveyard.
{1}, Exile Relic of Progenitus: Exile all graveyards. Draw a card.

Field Research

Kicker {2}{U} (You may pay an additional {2}{U} as you cast this spell.)
Draw two cards. If this spell was kicked, draw three cards instead.

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.)

Brainstorm

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

Deem Inferior

This spell costs {1} less to cast for each card you've drawn this turn.
The owner of target nonland permanent puts it into their library second from the top or on the bottom.

Secret Door

Defender
{4}{U}: Venture into the dungeon. Activate only as a sorcery. (Enter the first room or advance to the next room.)

Arms of Hadar

Creatures target player controls get -2/-2 until end of turn.

Basilica Stalker

Flying
Whenever Basilica Stalker deals combat damage to a player, you gain 1 life and surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Disguise {4}{B} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Thraben Charm

Choose one —
• Thraben Charm deals damage equal to twice the number of creatures you control to target creature.
• Destroy target enchantment.
• Exile any number of target players' graveyards.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Striped Riverwinder

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Cycling {U} ({U}, Discard this card: Draw a card.)

Lórien Revealed

Draw three cards.
Islandcycling {1} ({1}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Phantom Interference

Spree (Choose one or more additional costs.)
+ {3} — Create a 2/2 white Spirit creature token with flying.
+ {1} — Counter target spell unless its controller pays {2}.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Aven Fleetwing

Flying
Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Rakish Scoundrel

Deathtouch
When Rakish Scoundrel enters or is turned face up, target creature gains indestructible until end of turn.
Disguise {4}{B/G}{B/G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Hidden Strings

You may tap or untap target permanent, then you may tap or untap another target permanent.
Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

Pondering Mage

When Pondering Mage enters, look at the top three cards of your library, then put them back in any order. You may shuffle. Draw a card.

Deny Reality

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Return target permanent to its owner's hand.

Goliath Paladin

Vigilance
When Goliath Paladin enters, you take the initiative.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Staunch Throneguard

Vigilance
When Staunch Throneguard enters, you become the monarch.

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Thorn of the Black Rose

Deathtouch
When Thorn of the Black Rose enters, you become the monarch.

Island

Careful Study

Fetid Gargantua

{2}{B}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)
Whenever one or more +1/+1 counters are put on Fetid Gargantua, you may draw two cards. If you do, you lose 2 life.

Crimson Fleet Commodore

Trample
When Crimson Fleet Commodore enters, you become the monarch.

Unfathomable Truths

Devoid (This card has no color.)
Draw three cards and create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this creature: Add {C}."

Skulduggery

Until end of turn, target creature you control gets +1/+1 and target creature an opponent controls gets -1/-1.

Rewind

Counter target spell. Untap up to four lands.

Slip On the Ring

Exile target creature you own, then return it to the battlefield under your control. The Ring tempts you.

Orzhov Basilica

Orzhov Basilica enters tapped.
When Orzhov Basilica enters, return a land you control to its owner's hand.
{T}: Add {W}{B}.

Hookblade Veteran

During your turn, Hookblade Veteran has flying. (It can't be blocked except by creatures with flying or reach.)

Swamp

Hydroblast

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

Kami of Jealous Thirst

Deathtouch
{4}{B}: Each opponent loses 2 life and you gain 2 life. This ability costs {4}{B} less to activate if you've drawn three or more cards this turn. Activate only once each turn.

Troll of Khazad-dûm

Troll of Khazad-dûm can't be blocked except by three or more creatures.
Swampcycling {1} ({1}, Discard this card: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.)

Ponder

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

Into the Roil

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Return target nonland permanent to its owner's hand. If this spell was kicked, draw a card.

The Black Breath

Creatures your opponents control get -1/-1 until end of turn. The Ring tempts you.

Dinrova Horror

When Dinrova Horror enters, return target permanent to its owner's hand, then that player discards a card.