Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Mutagenic Growth

({G/P} can be paid with either {G} or 2 life.)
Target creature gets +2/+2 until end of turn.

Counterspell

Mountain

Island

Vapor Snag

Return target creature to its owner's hand. Its controller loses 1 life.

Rift Bolt

Rift Bolt deals 3 damage to any target.
Suspend 1—{R} (Rather than cast this card from your hand, you may pay {R} and exile it with a time counter on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Brainstorm

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

Highland Lake

Highland Lake enters tapped.
{T}: Add {U} or {R}.

Izzet Guildgate

Izzet Guildgate enters tapped.
{T}: Add {U} or {R}.

Spellweaver Eternal

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Afflict 2 (Whenever this creature becomes blocked, defending player loses 2 life.)

Bloodwater Entity

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Bloodwater Entity enters, you may put target instant or sorcery card from your graveyard on top of your library.

Electrickery

Electrickery deals 1 damage to target creature you don't control.
Overload {1}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Dwarven Forge-Chanter

Ward—Pay 2 life. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays 2 life.)
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)