Have

Consider

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

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}.)

Boomerang

Return target permanent to its owner's hand.

Foil

You may discard an Island card and another card rather than pay this spell's mana cost.
Counter target spell.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform this creature.

Delver of Secrets // Insectile Aberration

Island

Hard Evidence

Create a 0/3 blue Crab creature token.
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Counterspell

Cryptic Serpent

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

Brainstorm

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

Serpentine Curve

Create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it, where X is one plus the total number of instant and sorcery cards you own in exile and in your graveyard.

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Thought Scour

Target player mills two cards.
Draw a card.

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.)

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Deem Inferior

This spell costs {1} less to cast for each card you've drawn this turn.
The owner of target nonland permanent puts it into their library second from the top or on the bottom.