Sure Strike

Target creature gets +3/+0 and gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Vadrik, Astral Archmage

If it's neither day nor night, it becomes day as Vadrik, Astral Archmage enters.
Instant and sorcery spells you cast cost {X} less to cast, where X is Vadrik's power.
Whenever day becomes night or night becomes day, put a +1/+1 counter on Vadrik.

Muse Drake

Flying
When Muse Drake enters, draw a card.

Leapfrog

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

Izzet Guildgate

This land enters tapped.
{T}: Add {U} or {R}.

Geistlight Snare

This spell costs {1} less to cast if you control a Spirit. It also costs {1} less to cast if you control an enchantment.
Counter target spell unless its controller pays {3}.

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.

Glint-Horn Buccaneer

Haste
Whenever you discard a card, Glint-Horn Buccaneer deals 1 damage to each opponent.
{1}{R}, Discard a card: Draw a card. Activate only if Glint-Horn Buccaneer is attacking.

Ral's Staticaster

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever Ral's Staticaster attacks, if you control a Ral planeswalker, Ral's Staticaster gets +1/+0 for each card in your hand until end of turn.

Serpentine Ambush

Until end of turn, target creature becomes a blue Serpent with base power and toughness 5/5.

Mountain

Omnispell Adept

{2}{U}, {T}: You may cast an instant or sorcery spell from your hand without paying its mana cost.

Sonic Assault

Tap target creature. Sonic Assault deals 2 damage to that creature's controller.
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.)

Wee Dragonauts

Flying
Whenever you cast an instant or sorcery spell, Wee Dragonauts gets +2/+0 until end of turn.

Storm Skreelix

Flying
Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, Storm Skreelix gets +2/+0 until end of turn.

Ral, Caller of Storms

+1: Draw a card.
−2: Ral, Caller of Storms deals 3 damage divided as you choose among one, two, or three targets.
−7: Draw seven cards. Ral, Caller of Storms deals 7 damage to each creature your opponents control.

Scattered Thoughts

Look at the top four cards of your library. Put two of those cards into your hand and the rest into your graveyard.

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

Fire Urchin

Trample
Whenever you cast an instant or sorcery spell, Fire Urchin gets +1/+0 until end of turn.

Brimstone Vandal

Menace (This creature can't be blocked except by two or more creatures.)
If it's neither day nor night, it becomes day as Brimstone Vandal enters.
Whenever day becomes night or night becomes day, Brimstone Vandal deals 1 damage to each opponent.

Thirst for Discovery

Draw three cards. Then discard two cards unless you discard a basic land card.

Wash Away

Cleave {1}{U}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Counter target spell [that wasn't cast from its owner's hand].

Play with Fire

Play with Fire deals 2 damage to any target. If a player is dealt damage this way, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Ral's Dispersal

Return target creature to its owner's hand. You may search your library and/or graveyard for a card named Ral, Caller of Storms, reveal it, and put it into your hand. If you search your library this way, shuffle.

Island

Quasiduplicate

Create a token that's a copy of target creature you control.
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.)

Lunar Frenzy

Target creature you control gets +X/+0 and gains first strike and trample until end of turn.