Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Syndicate Messenger

Flying
Afterlife 1 (When this creature dies, create a 1/1 white and black Spirit creature token with flying.)

Mourning Thrull

({W/B} can be paid with either {W} or {B}.)
Flying
Whenever Mourning Thrull deals damage, you gain that much life.

Compulsive Research

Target player draws three cards. Then that player discards two cards unless they discard a land card.

Angelic Exaltation

Whenever a creature you control attacks alone, it gets +X/+X until end of turn, where X is the number of creatures you control.

Vedalken Mesmerist

Whenever Vedalken Mesmerist attacks, target creature an opponent controls gets -2/-0 until end of turn.

Armory Guard

Armory Guard has vigilance as long as you control a Gate.

Urbis Protector

When Urbis Protector enters the battlefield, create a 4/4 white Angel creature token with flying.

Judge's Familiar

Flying
Sacrifice Judge's Familiar: Counter target instant or sorcery spell unless its controller pays {1}.

Basilica Guards

Defender
Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Cloudfin Raptor

Flying
Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Quench

Counter target spell unless its controller pays {2}.

Sphinx's Revelation

Pteramander

Flying
{7}{U}: Adapt 4. This ability costs {1} less to activate for each instant and sorcery card in your graveyard. (If this creature has no +1/+1 counters on it, put four +1/+1 counters on it.)

Deathrite Shaman

{T}: Exile target land card from a graveyard. Add one mana of any color.
{B}, {T}: Exile target instant or sorcery card from a graveyard. Each opponent loses 2 life.
{G}, {T}: Exile target creature card from a graveyard. You gain 2 life.

Keymaster Rogue

Keymaster Rogue can't be blocked.
When Keymaster Rogue enters the battlefield, return a creature you control to its owner's hand.

Repeal

Return target nonland permanent with mana value X to its owner's hand.
Draw a card.

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Radical Idea

Draw a card.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Voyager Staff

{2}, Sacrifice Voyager Staff: Exile target creature. Return the exiled card to the battlefield under its owner's control at the beginning of the next end step.

Warden

Create a 4/4 white and blue Sphinx creature token with flying and vigilance.

Warrant

Put target attacking or blocking creature on top of its owner's library.

Warrant // Warden

Greater Forgeling

{1}{R}: Greater Forgeling gets +3/-3 until end of turn.

Island

Deputy of Acquittals

Flash (You may cast this spell any time you could cast an instant.)
When Deputy of Acquittals enters the battlefield, you may return another target creature you control to its owner's hand.

Debt to the Deathless

Each opponent loses two times X life. You gain life equal to the life lost this way.

Eyes in the Skies

Create a 1/1 white Bird creature token with flying, then populate. (Create a token that's a copy of a creature token you control.)

Plains

Bulwark Giant

When Bulwark Giant enters the battlefield, you gain 5 life.

Selesnya Guildgate

Selesnya Guildgate enters the battlefield tapped.
{T}: Add {G} or {W}.

Persistent Petitioners

{1}, {T}: Target player mills a card. (They put the top card of their library into their graveyard.)
Tap four untapped Advisors you control: Target player mills twelve cards.
A deck can have any number of cards named Persistent Petitioners.

Totally Lost

Put target nonland permanent on top of its owner's library.

Act of Treason

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Makeshift Battalion

Battalion — Whenever Makeshift Battalion and at least two other creatures attack, put a +1/+1 counter on Makeshift Battalion.

Azorius Guildgate

Azorius Guildgate enters the battlefield tapped.
{T}: Add {W} or {U}.

Savra, Queen of the Golgari

Whenever you sacrifice a black creature, you may pay 2 life. If you do, each other player sacrifices a creature.
Whenever you sacrifice a green creature, you may gain 2 life.

Helium Squirter

Graft 3 (This creature enters the battlefield with three +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)
{1}: Target creature with a +1/+1 counter on it gains flying until end of turn.

Leapfrog

Leapfrog has flying as long as you've cast an instant or sorcery spell this turn.

Whisper Agent

Flash
When Whisper Agent enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Coiling Oracle

When Coiling Oracle enters the battlefield, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

Drift of Phantasms

Defender (This creature can't attack.)
Flying
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)