Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.
When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

Mountain

Psychic Corrosion

Whenever you draw a card, each opponent mills two cards.

The Watcher in the Water

The Watcher in the Water enters tapped with nine stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you draw a card during an opponent's turn, create a 1/1 blue Tentacle creature token.
Whenever a Tentacle you control dies, untap up to one target Kraken and put a stun counter on up to one target nonland permanent.

Magmatic Insight

As an additional cost to cast this spell, discard a land card.
Draw two cards.

Seething Song

Ur-Golem's Eye

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

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.)

Serum Visions

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet, Parun deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Runaway Steam-Kin

Whenever you cast a red spell, if Runaway Steam-Kin has fewer than three +1/+1 counters on it, put a +1/+1 counter on Runaway Steam-Kin.
Remove three +1/+1 counters from Runaway Steam-Kin: Add {R}{R}{R}.

Inner Fire

Finale of Revelation

Draw X cards. If X is 10 or more, instead shuffle your graveyard into your library, draw X cards, untap up to five lands, and you have no maximum hand size for the rest of the game.
Exile Finale of Revelation.

Thran Dynamo

Thought Vessel

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

Peek

Look at target player's hand.
Draw a card.

Thought Reflection

If you would draw a card, draw two cards instead.

Rewind

Counter target spell. Untap up to four lands.

Peregrine Drake

Flying
When Peregrine Drake enters, untap up to five lands.

Ponder

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

Cloud of Faeries

Flying
When Cloud of Faeries enters, untap up to two lands.
Cycling {2} ({2}, Discard this card: Draw a card.)

Crimson Wisps

Target creature becomes red and gains haste until end of turn. (It can attack and {T} this turn.)
Draw a card.

Exotic Orchard

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

Mana Geyser

Add {R} for each tapped land your opponents control.

Rite of Flame

Add {R}{R}, then add {R} for each card named Rite of Flame in each graveyard.

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Teferi's Tutelage

When Teferi's Tutelage enters, draw a card, then discard a card.
Whenever you draw a card, target opponent mills two cards. (They put the top two cards of their library into their graveyard.)

Jace's Erasure

Whenever you draw a card, you may have target player mill a card.

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Pyretic Ritual

Crash Through

Creatures you control gain trample until end of turn. (Each of those creature can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.

Command Tower

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

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Arcane Signet

Sisay's Ring

The Irencrag

{T}: Add {C}.
Whenever a legendary creature you control enters, you may have The Irencrag become a legendary Equipment artifact named Everflame, Heroes' Legacy. If you do, it gains equip {3} and "Equipped creature gets +3/+3" and loses all other abilities.

Sol Ring

Expedite

Target creature gains haste until end of turn.
Draw a card.

Battle Hymn

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Vindictive Flamestoker

Whenever you cast a noncreature spell, put an oil counter on Vindictive Flamestoker.
{6}{R}, Sacrifice Vindictive Flamestoker: Discard your hand, then draw four cards. This ability costs {1} less to activate for each oil counter on Vindictive Flamestoker.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Island

Ominous Seas

Whenever you draw a card, put a foreshadow counter on Ominous Seas.
Remove eight foreshadow counters from Ominous Seas: Create an 8/8 blue Kraken creature token.
Cycling {2} ({2}, Discard this card: Draw a card.)

Quicken

The next sorcery spell you cast this turn can be cast as though it had flash. (It can be cast any time you could cast an instant.)
Draw a card.

Brainstorm

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

Cosmium Catalyst

{1}{R}, {T}: Choose an exiled card used to craft Cosmium Catalyst at random. You may cast that card without paying its mana cost.

Ore-Rich Stalactite

{T}: Add {R}. Spend this mana only to cast an instant or sorcery spell.
Craft with four or more red instant and/or sorcery cards {3}{R}{R} ({3}{R}{R}, Exile this artifact, Exile the four or more from your graveyard: Return this card transformed under its owner's control. Craft only as a sorcery.)

Ore-Rich Stalactite // Cosmium Catalyst

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Izzet Signet

Unwind

Counter target noncreature spell. Untap up to three lands.

Fellwar Stone

Snap

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

Renegade Tactics

Target creature can't block this turn.
Draw a card.

Mindmoil

Whenever you cast a spell, put the cards in your hand on the bottom of your library in any order, then draw that many cards.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Ferrous Lake

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet, the Firemind deals 1 damage to any target.
{T}: Draw a card.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Arjun, the Shifting Flame

Flying
Whenever you cast a spell, put the cards in your hand on the bottom of your library in any order, then draw that many cards.

Finale of Promise

You may cast up to one target instant card and/or up to one target sorcery card from your graveyard each with mana value X or less without paying their mana costs. If a spell cast this way would be put into your graveyard, exile it instead. If X is 10 or more, copy each of those spells twice. You may choose new targets for the copies.

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

Sphinx's Tutelage

Whenever you draw a card, target opponent mills two cards. If two nonland cards that share a color were milled this way, repeat this process.
{5}{U}: Draw a card, then discard a card.

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Izzet Boilerworks

Izzet Boilerworks enters tapped.
When Izzet Boilerworks enters, return a land you control to its owner's hand.
{T}: Add {U}{R}.

The Locust God

Flying
Whenever you draw a card, create a 1/1 blue and red Insect creature token with flying and haste.
{2}{U}{R}: Draw a card, then discard a card.
When The Locust God dies, return it to its owner's hand at the beginning of the next end step.

Frostboil Snarl

As Frostboil Snarl enters, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters tapped.
{T}: Add {U} or {R}.