Protean Thaumaturge

Constellation — Whenever an enchantment enters the battlefield under your control, you may have Protean Thaumaturge become a copy of another target creature, except it has this ability.

Triumph of the Hordes

Until end of turn, creatures you control get +1/+1 and gain trample and infect. (Creatures with infect deal damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Arrester’s Zeal

Target creature gets +2/+2 until end of turn.
Addendum — If you cast this spell during your main phase, that creature gains flying until end of turn.

Grasp of Phantoms

Put target creature on top of its owner’s library.
Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Crown-Hunter Hireling

When Crown-Hunter Hireling enters the battlefield, you become the monarch.
Crown-Hunter Hireling can’t attack unless defending player is the monarch.

Frost Lynx

When Frost Lynx enters the battlefield, tap target creature an opponent controls. That creature doesn’t untap during its controller’s next untap step.

Unlicensed Disintegration

Destroy target creature. If you control an artifact, Unlicensed Disintegration deals 3 damage to that creature’s controller.

Atarka Efreet

Megamorph (You may cast this card face down as a 2/2 creature for . Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Atarka Efreet is turned face up, it deals 1 damage to any target.

Winding Constrictor

If one or more counters would be put on an artifact or creature you control, that many plus one of each of those kinds of counters are put on that permanent instead.
If you would get one or more counters, you get that many plus one of each of those kinds of counters instead.

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Shardless Agent

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 of your library in a random order.)

Filigree Familiar

When Filigree Familiar enters the battlefield, you gain 2 life.
When Filigree Familiar dies, draw a card.

Take Down

Choose one —
• Take Down deals 4 damage to target creature with flying.
• Take Down deals 1 damage to each creature with flying.

Uncomfortable Chill

Creatures your opponents control get -2/-0 until end of turn.
Draw a card.

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Sensor Splicer

When Sensor Splicer enters the battlefield, create a 3/3 colorless Golem artifact creature token.
Golem creatures you control have vigilance.

Crash Through

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

Raging Swordtooth

Trample
When Raging Swordtooth enters the battlefield, it deals 1 damage to each other creature.

Nightmare Unmaking

Choose one —
• Exile each creature with power greater than the number of cards in your hand.
• Exile each creature with power less than the number of cards in your hand.

Ghired’s Belligerence

Ghired’s Belligerence deals X damage divided as you choose among any number of target creatures. Whenever a creature dealt damage this way dies this turn, populate. (Create a token that’s a copy of a creature token you control.)