Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Mystic Sanctuary

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

Mindslaver

{4}, {T}, Sacrifice Mindslaver: You control target player during that player's next turn. (You see all cards that player could see and make all decisions for the player.)

Bribery

Search target opponent's library for a creature card and put that card onto the battlefield under your control. Then that player shuffles.

Thought Vessel

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

Sapphire Medallion

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

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.

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.)

Blatant Thievery

For each opponent, gain control of target permanent that player controls.

Propaganda

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

Freed from the Real

Enchant creature
{U}: Tap enchanted creature.
{U}: Untap enchanted creature.

Personal Tutor

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

Puppeteer

{U}, {T}: You may tap or untap target creature.

Sakashima of a Thousand Faces

You may have Sakashima of a Thousand Faces enter 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.)

Control Magic

Enchant creature
You control enchanted creature.

Empress Galina

{U}{U}, {T}: Gain control of target legendary permanent. (This effect lasts indefinitely.)

Archmage Ascension

At the beginning of each end step, if you drew two or more cards this turn, you may put a quest counter on Archmage Ascension.
As long as Archmage Ascension has six or more quest counters on it, if you would draw a card, you may instead search your library for a card, put that card into your hand, then shuffle.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

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.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Long-Term Plans

Search your library for a card, then shuffle and put that card third from the top.

Sower of Temptation

Flying
When Sower of Temptation enters, gain control of target creature for as long as Sower of Temptation remains on the battlefield.

Island

Sol Ring

Blue Sun's Twilight

Gain control of target creature with mana value X or less. If X is 5 or more, create a token that's a copy of that creature.

Howling Mine

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Reliquary Tower

Invoke the Winds

Gain control of target artifact or creature. Untap it.

Tunnel Vision

Choose a card name. Target player reveals cards from the top of their library until a card with that name is revealed. If it is, that player puts the rest of the revealed cards into their graveyard and puts the card with the chosen name on top of their library. Otherwise, the player shuffles.

Archmage's Charm

Choose one —
• Counter target spell.
• Target player draws two cards.
• Gain control of target nonland permanent with mana value 1 or less.

Dramatic Reversal

Untap all nonland permanents you control.

Counterspell

Thada Adel, Acquisitor

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Thada Adel, Acquisitor deals combat damage to a player, search that player's library for an artifact card and exile it. Then that player shuffles. Until end of turn, you may play that card.

Roil Elemental

Flying
Landfall — Whenever a land you control enters, you may gain control of target creature for as long as you control Roil Elemental.

Ponder

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

Expropriate

Council's dilemma — Starting with you, each player votes for time or money. For each time vote, take an extra turn after this one. For each money vote, choose a permanent owned by the voter and gain control of it. Exile Expropriate.

Lightning Greaves

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

Agent of Treachery

When Agent of Treachery enters, gain control of target permanent.
At the beginning of your end step, if you control three or more permanents you don't own, draw three cards.

Rhystic Study

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

Vedalken Shackles

You may choose not to untap Vedalken Shackles during your untap step.
{2}, {T}: Gain control of target creature with power less than or equal to the number of Islands you control for as long as Vedalken Shackles remains tapped.

Font of Mythos

At the beginning of each player's draw step, that player draws two additional cards.

Planar Portal

{6}, {T}: Search your library for a card, put that card into your hand, then shuffle.

Clever Impersonator

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

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Aura Thief

Flying
When Aura Thief dies, you gain control of all enchantments. (You don't get to move Auras.)

Thalakos Deceiver

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever Thalakos Deceiver attacks and isn't blocked, you may sacrifice it. If you do, gain control of target creature. (This effect lasts indefinitely.)

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Leyline of Singularity

If Leyline of Singularity is in your opening hand, you may begin the game with it on the battlefield.
All nonland permanents are legendary.

Trade Routes

{1}: Return target land you control to its owner's hand.
{1}, Discard a land card: Draw a card.

Memnarch

{1}{U}{U}: Target permanent becomes an artifact in addition to its other types. (This effect lasts indefinitely.)
{3}{U}: Gain control of target artifact. (This effect lasts indefinitely.)

Gather Specimens

If a creature would enter the battlefield under an opponent's control this turn, it enters under your control instead.

Arcane Lighthouse

{T}: Add {C}.
{1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

Halimar Depths

Halimar Depths enters tapped.
When Halimar Depths enters, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

Noble Benefactor

When Noble Benefactor dies, each player may search their library for a card and put that card into their hand. Then each player who searched their library this way shuffles.

Detection Tower

{T}: Add {C}.
{1}, {T}: Until end of turn, your opponents and creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.

Minamo, School at Water's Edge

{T}: Add {U}.
{U}, {T}: Untap target legendary permanent.

Ioreth of the Healing House

{T}: Untap another target permanent.
{T}: Untap two other target legendary creatures.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Brainstorm

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

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.

Diplomatic Immunity

Enchant creature
Shroud (A permanent with shroud can't be the target of spells or abilities.)
Enchanted creature has shroud.

Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."

Aphetto Alchemist

{T}: Untap target artifact or creature.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Jace, Ingenious Mind-Mage

+1: Draw a card.
+1: Untap all creatures you control.
−9: Gain control of up to three target creatures.