Consider

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

Annul

Counter target artifact or enchantment spell.

Thought Scour

Target player mills two cards.
Draw a card.

Cryptic Serpent

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.

Disrupt

Counter target instant or sorcery spell unless its controller pays {1}.
Draw a card.

Sneaky Snacker

Flying
When you draw your third card in a turn, return Sneaky Snacker from your graveyard to the battlefield tapped.

Brainstorm

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

Island

Steel Sabotage

Choose one —
• Counter target artifact spell.
• Return target artifact to its owner's hand.

Counterspell

Careful Study

Contaminated Aquifer

({T}: Add {U} or {B}.)
Contaminated Aquifer enters tapped.

Hydroblast

Choose one —
• Counter target spell if it's red.
• Destroy target permanent if it's red.

Tolarian Terror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Lórien Revealed

Draw three cards.
Islandcycling {1} ({1}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Boomerang

Return target permanent to its owner's hand.

Murmuring Mystic

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