Aetherling

{U}: Exile Aetherling. Return it to the battlefield under its owner's control at the beginning of the next end step.
{U}: Aetherling can't be blocked this turn.
{1}: Aetherling gets +1/-1 until end of turn.
{1}: Aetherling gets -1/+1 until end of turn.

Nightveil Sprite

Flying
Whenever Nightveil Sprite attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Dakra Mystic

{U}, {T}: Each player reveals the top card of their library. You may put the revealed cards into their owners' graveyards. If you don't, each player draws a card.

Neurok Commando

Shroud (This creature can't be the target of spells or abilities.)
Whenever Neurok Commando deals combat damage to a player, you may draw a card.

Tetsuko Umezawa, Fugitive

Creatures you control with power or toughness 1 or less can't be blocked.

Jhessian Thief

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Jhessian Thief deals combat damage to a player, draw a card.

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Mist-Syndicate Naga

Ninjutsu {2}{U} ({2}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Mist-Syndicate Naga deals combat damage to a player, create a token that's a copy of Mist-Syndicate Naga.

Scroll Thief

Whenever Scroll Thief deals combat damage to a player, draw a card.

Daring Saboteur

{2}{U}: Daring Saboteur can't be blocked this turn.
Whenever Daring Saboteur deals combat damage to a player, you may draw a card. If you do, discard a card.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Hypnotic Siren

Bestow {5}{U}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Flying
You control enchanted creature.
Enchanted creature gets +1/+1 and has flying.

Mindshrieker

Flying
{2}: Target player mills a card. Mindshrieker gets +X/+X until end of turn, where X is the milled card's mana value.

Teferi's Veil

Whenever a creature you control attacks, it phases out at end of combat. (While it's phased out, it's treated as though it doesn't exist. It phases in before you untap during your next untap step.)

Renegade Doppelganger

Whenever another creature enters the battlefield under your control, you may have Renegade Doppelganger become a copy of that creature until end of turn. (If it does, it loses this ability for the rest of the turn.)

Coastal Piracy

Whenever a creature you control deals combat damage to an opponent, you may draw a card.

Failed Inspection

Counter target spell. Draw a card, then discard a card.

Scion of Glaciers

{U}: Scion of Glaciers gets +1/-1 until end of turn.

Surrakar Spellblade

Whenever you cast an instant or sorcery spell, you may put a charge counter on Surrakar Spellblade.
Whenever Surrakar Spellblade deals combat damage to a player, you may draw X cards, where X is the number of charge counters on it.

Repulse

Return target creature to its owner's hand.
Draw a card.

Commence the Endgame

This spell can't be countered.
Draw two cards, then amass Zombies X, where X is the number of cards in your hand. (Put X +1/+1 counters on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)

Jace, Cunning Castaway

+1: Whenever one or more creatures you control deal combat damage to a player this turn, draw a card, then discard a card.
−2: Create a 2/2 blue Illusion creature token with "When this creature becomes the target of a spell, sacrifice it."
−5: Create two tokens that are copies of Jace, Cunning Castaway, except they're not legendary.

Dismiss

Jeskai Elder

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Jeskai Elder deals combat damage to a player, you may draw a card. If you do, discard 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.

Open into Wonder

X target creatures can't be blocked this turn. Until end of turn, those creatures gain "Whenever this creature deals combat damage to a player, draw a card."

Water Servant

{U}: Water Servant gets +1/-1 until end of turn.
{U}: Water Servant gets -1/+1 until end of turn.

Dream Fracture

Counter target spell. Its controller draws a card.
Draw a card.

Pull from Tomorrow

Counterspell

Gateway Sneak

Whenever a Gate enters the battlefield under your control, Gateway Sneak can't be blocked this turn.
Whenever Gateway Sneak deals combat damage to a player, draw a card.

Precognitive Perception

Draw three cards.
Addendum — If you cast this spell during your main phase, instead scry 3, then draw three cards.

Shorecrasher Elemental

{U}: Exile Shorecrasher Elemental, then return it to the battlefield face down under its owner's control.
{1}: Shorecrasher Elemental gets +1/-1 or -1/+1 until end of turn.
Megamorph {4}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)